The Finn was able to pass an aggressive Nico Rosberg late in the race as both Mercedes suffered with brake problems.
Sebastian Vettel's hard work in qualifying second was undone late in the race, as the German was forced to stop for a new wing following an error late in the race, leaving him fifth behind Valtteri Bottas.
Daniel Ricciardo came home sixth despite his Renault engine dying on the final corner
PRACTICE AND QUALIFYING
Ferrari's continuing progress towards the front showed itself again during the practice sessions, with both Raikkonen and Vettel featuring among the Mercedes.
Vettel's Friday night session was interrupted with a silly accident coming out of the pits (with a suspected wobbly wheel), the German tangling with Force India's Perez.
Qualifying was a thriller, with Hamilton snatching pole in the dying seconds, Vettel splitting the Mercedes and Raikkonen remonstrating with himself for underestimating the grip levels.
Daniel Ricciardo followed the two Williams, coming seventh but comprehensively out-qualifying Kvyat who could only manage seventeenth ahead of two Manors and Button's McLaren which failed on its out lap.
Alonso had a better time, making it into Q2 and fourteenth while Carlos Sainz outshone Verstappen for P9.
As the clock ticked over to 6pm local time only eighteen cars headed off on the formation lap - Felipe Massa's Williams sat stranded on the grid with a suspected electrical problem. Jenson Button didn't even make it out on the grid.
The lights went out and Hamilton and Vettel dragged down to the first corner, the Mercedes winning. The second silver arrow lost out to a hard-starting Raikkonen who elbowed his way past around the outside.
Pastor Maldonado had an eventful first lap, spending as much time out in the dust as on the track and even walloping Max Verstappen into the bargain. Despite his raggedness, he got by Daniil Kvyat in the second Red Bull.
Maldonado was soon under investigation for using the wrong grid slot. He got a five second time penalty for his trouble.
Bottas and Ricciardo held station while Marcus Ericsson and Fernando Alonso picked up places.
Hamilton set about getting out of DRS range by the time the feature was activated, holding a 1.5 second gap to Vettel by lap four.
Rosberg wasn't content behind Raikkonen and launched a move down the inside of the Finn at turn one, a "yield or crash" manoeuvre. It was messy, tyre smokey, but it worked.
Massa was on full attack after his disastrous start, passing Alonso on lap six.
Verstappen came in on lap seven for a long stop that included a new nose and a quick inspection after his contact with Maldonado. The Dutchman's teammate would later have a long stop too, after copping a penalty for breaking an obscure rule - spending too much time on his recce lap before the race.
Rosberg was almost gifted second by Vettel after the German outbraked himself. He held the place for a lap but the Mercedes' DRS-assisted straight line speed and Rosberg's need to prove a point saw the place changes hands.
On lap ten, Raikkonen radioed in to tell his pitwall matter-of-factly that he would try and overtake Vettel as he was going faster.
Hulkenberg and Nasr pitted on lap eleven, indicating the slightly riskier decision to go for a three-stop strategy. Nasr's road into the pits wasn't an easy one as Felipe Massa battled for his place.
With Ericsson also pitting, Daniil Kvyat made it into the top ten, pursued by Fernando Alonso's McLaren. Maldonado pitted for medium tyres and the Veneuzuelan threw down a couple of quick laps.
Vettel pitted on lap fourteen, fitting soft tyres and trying to undercut Rosberg. Alonso came in for mediums to try the same trick on Kvyat, and it was succssful. Out on track, Romain Grosjean stuck a move on Hulkenberg into turn one.
Mercedes responded by pitting Rosberg before Hamilton but it was to no avail, Vettel's gigantic out lap got him ahead of his compatriot. Hamilton came in a lap later on fifteen, leaving Raikkonen out in the lead.
As Hamilton popped out of the pits, he had Rosberg and Vettel fighting over second place rather closer than he might have wanted, given his previous six second lead - a slow stop destroyed his lead. The first Ferrari and second Mercedes had dived towards the pitwall, sparks flying from the skidblocks, with Rosberg winning the braking battle into turn one.
Raikkonen pitted on lap eighteen for medium tyres. The Finn pulled out of pitlane ahead of fifth-placed Bottas. Raikkonen's was a shrewd strategic move, hoping to find himself on fresher tyres later in the race.
The race at the front settled for a time after the tyre stops, but the three cars were covered by less than two seconds, a state of affairs thought very unlikely not so long ago.
The rhyming Brazilians of Felipe Massa and Felipe Nasr were locked in combat for the final point in tenth for many laps, the older of the two gamely hanging on as he also pursued Hulkenberg in ninth.
On lap twenty-five Nasr spotted a weakness and dived past, only to pit with his countryman moments later.
Both were followed in by Maldonado who managed to come out in front of both the Williams and the Sauber. Nasr had been held with a sticky left rear, Massa by a cautious stop.
Hulkenberg pitted for primes a lap later and Ericsson for softs. Ericsson's stop went on forever after the left front wheel refused to fix itself to the hub. Hulkenberg's stop worked well for him, slotting between the Lotus of Maldonado and the Williams of Massa.
Vettel was struggling in his Ferrari - he again ran wide, allowing Raikkonen to draw ever closer.
Carlos Sainz briefly brought out yellow flags in sector two on lap 31 after slowing to a halt following a pit stop, his fine qualifying performance ruined by his own pre-race error and a badly-fitted wheel.
Vettel pitted at the end of lap thirty two for a super-quick stop. Raikkonen, meanwhile, was arguing with his pitwall about the choice of moving to the soft tyres - Kimi wanted to stay on the medium that had done him so well. The pitwall won.
Hamilton pitted a lap later for medium tyres to take him to the end. Bottas did the same as did Rosberg the following lap.
Once again Vettel ended up ahead of Rosberg's Mercedes after the pit stops. Rosberg didn't have to wait long as the Ferrari slipped off the road at the final corner, giving the Mercedes driver an easy path into second place.
Vettel radioed to tell Ferrari that he had damage and in he came for a new front wing and a fresh set of mediums.
Once again, Max Verstappen's race ended early, this time on lap 36 with a suspected electrical problem.
After the pit stops, Raikkonen was again in the lead, with Hamilton hunting him down, the two cars separated by Fernando Alonso in his lapped McLaren. The Honda-powered car got past the Ferrari as the tyres faded and Hamilton closed in and passed on lap forty, the Finn quickly falling away before pitting at the end of the lap for soft tyres.
He was stationary for just 2.3 seconds.
Maldonado pitted for the final time on lap 43. The Lotus driver's race ended there with smoke pouring from his brakes. The Venezuelan had been fast but wayward, colliding with Verstappen and Massa early in the race.
Vettel drew close to Bottas but got no further, the Mercedes-powered Williams holding the German at bay.
With eleven laps to go, Raikkonen was ten seconds behind Nico Rosberg, reeling him in. Nico asked his team to stop telling him the gap as the Finn knocked a few seconds out of the gap.
Raikkonen whittled away the gap and Rosberg was told to lift and coast to save fuel and brakes.
Raikkonen caught Rosberg on lap 55 of 57 and applied the pressure. Rosberg ran wide at the beginning lap 56 and Raikkonen slipped past. Rosberg fought back but the places were now decided.
A jubilant Hamilton crossed the line to continue his winning ways, followed home by the Ferrari of Raikkonen, Rosberg third.
Daniel Ricciardo's weekend finished with sixth place and also ended his third of four Renault engines for the year, the engine letting go just as the Australian rounded the final corner.
"I think the race went as well as it could and I drove well to finish sixth. The chassis is working better and through the corners we are more or less there; we'll move onto Europe and see if we can get further up the grid and keep improving," Ricciardo said.
"The weekend went pretty smooth for me until the end of the race, I don't know what happened, but the team will have a look at it."
Formula 1 returns to Europe in three weeks for the Spanish Grand Prix.
2015 Bahrain F1 GP Results
- Lewis Hamilton - Mercedes - 1h35m05.809s
- Kimi Raikkonen - Ferrari +3.380s
- Nico Rosberg - Mercedes +6.033s
- Valtteri Bottas - Williams/Mercedes +42.957s
- Sebastian Vettel - Ferrari +43.989s
- Daniel Ricciardo - Red Bull/Renault +1m01.751s
- Romain Grosjean - Lotus/Mercedes +1m24.763s
- Sergio Perez - Force India/Mercedes +1 Lap
- Daniil Kvyat - Red Bull/Renault +1 Lap
- Felipe Massa - Williams/Mercedes +1 Lap
- Fernando Alonso - McLaren/Honda +1 Lap
- Felipe Nasr - Sauber/Ferrari +1 Lap
- Nico Hulkenberg - Force India/Mercedes +1 Lap
- Marcus Ericsson - Sauber/Ferrari +1 Lap
- Pastor Maldonado - Lotus/Mercedes +1 Lap
- Will Stevens - Marussia/Ferrari +2 Laps
- Roberto Merhi - Marussia/Ferrari +3 Laps
- Max Verstappen - Toro Rosso/Renault - Retirement
- Carlos Sainz - Toro Rosso/Renault - Retirement
- Jenson Button - McLaren/Honda - Not started
MORE: 2015 F1 Race Coverage