Mercedes driver Hamilton capitalised on his sixth consecutive pole position, and 10th in 11 season races, to storm to his sixth campaign victory in one hour 23 minutes 4.387 seconds around the 43 laps of the 7.004-kilometre Spa-Francorchamps circuit.
Nico Rosberg followed his Mercedes team-mate Hamilton over the line, 2.058 seconds behind, while Romain Grosjean took surprise third for Lotus, and celebrated wildly with his team.
Hamilton now leads the standings on 227 points with Rosberg on 199.
Ferrari’s Sebastian Vettel remains third on 160 after a bold move to complete the race on just one pit stop failed on the penultimate lap.
“An amazing weekend again, it was an incredible job done by the team,” Hamilton said on the podium after his 39th career win. “Today was a dream and the car was fantastic all weekend.”
Rosberg was left to reflect on another second place and a gap to Hamilton in the standings which now cannot be bridged in just one race.
“Lewis did a great job and deserved the win,” he said. “I tried to challenge him but not enough.
“I am rushing off after this because we are expecting our first child any moment. It is an exciting time and I look forward to next week.”
A nervous start was expected under new procedures which restrict communication between drivers and their garages on the formation lap and prevents engineers helping drivers adjust the clutch biting point.
Force India’s Nico Huelkenberg lost power on the grid before the start, requiring an extra formation lap. He promptly retired and was soon joined by Pastor Maldanado of Lotus, wasting a high qualifying position of seventh.
While Hamilton had no trouble getting away, Rosberg struggled badly and slipped from second to fifth as he lost ground to Sergio Perez in Force India, Valtteri Bottas of Williams and Red Bull’s Daniel Ricciardo.
Rosberg recovered to third, behind Perez, and when the latter driver pitted on lap eight, Rosberg’s quicker stop a lap later allowed him to come out in front.
That gave him a view of the back of Hamilton and though he closed to within just over two seconds after a virtual safety car following Ricciardo losing power and retiring on lap 21, he was never close enough to threaten.
Hamilton ramped up the speed to lead by nearly five seconds after 26 laps before pitting for the second and final time on lap 30. When he regained the lead from Rosberg’s lap 31 pit with an advantage of 7.5 seconds, victory was assured.
Vettel, who started eighth in the grid, attempted a brave race and even led briefly before pitting for the first time. While a repeat of his win from the previous Hungarian Grand Prix was never likely, he held on to third for 28 laps on a single set of tyres after making his solitary stop.
When his right rear tyre finally blew on the 42nd of the 43 laps, Grosjean, who had been on his tail throughout, had a simple task to claim an 10th career podium place.
Red Bull’s Daniil Kvyat finished fourth ahead of Perez, Felipe Massa took sixth in a Williams and Kimi Raikkonen, in the other Ferrari finished seventh despite starting 16th due to a gearbox change penalty.
Bottas’s chance of a truly high finish vanished on lap 13 when his team fitted a mixture of tyres during a stop. He was given a drive-through penalty for the violation and failed to trouble the podium places from then on though recovered to claim ninth behind Toro Rosso’s Max Verstappen.
Sauber’s Marcus Ericsson completed the points placings in 10th. His team-mate Felipe Nasr was 11th and Vettel limped home 12th with only three functioning tyres.
The McLaren duo Fernando Alonso and Jenson Button moved up from the back of the grid to take 13th and 14th, after massive starting penalties for engine changes, ahead of Manor pair Roberto Merhi and Will Stevens.
Carlos Sainz, in the other Toro Rosso, joined Ricciardo, Huelkenberg and Maldanado in failing to finish.
The next race is the Italian Grand Prix on September 6.
Original source: Hamilton triumphs in Belgium