The Briton lapped the Albert Park circuit in a searing one minute and 21.164 seconds to cross the line 0.664 seconds clear of Ferrari's Kimi Raikkonen.
Hamilton will equal Ferrari great Michael Schumacher's all-time win record if he takes his seventh win of the season on Sunday.
Finland's Valtteri Bottas seized the first Formula One victory of his career at the Russian Grand Prix on Sunday after jumping both Ferraris at the start and then holding his nerve over the tense closing laps.
Hamilton wrapped up his record-equalling seventh title in Turkey last month and picked up his 11th win of the season in Bahrain on Sunday. Mercedes have already won the constructors' title for an unprecedented seventh year in a row.
Given how well Hamilton drove last weekend to win the Styrian GP in Austria, few would bet against the British driver securing an eighth success
Daniel Ricciardo dashed Red Bull team mate Max Verstappen's hopes of becoming Formula One's youngest ever pole-sitter on Saturday while championship leader Lewis Hamilton qualified third for Mercedes at the Mexican Grand Prix. Hamilton, who need only finish seventh on Sunday to secure his fifth title with two races to spare, will have Ferrari rival Sebastian Vettel alongside on the second row.
Triple world champion Lewis Hamilton took a record 69th Formula One pole position with a wet weather masterclass at the Italian Grand Prix.
Valtteri Bottas took pole position for Formula One's 70th Anniversary Grand Prix ahead of championship-leading Mercedes team mate Lewis Hamilton on Saturday.
Ferrari's Charles Leclerc, starting on pole, finished second after defending hard against Verstappen with the two 21-year-olds banging wheels as the Dutchman forced his way past. Verstappen took the flag under investigation.
Hamilton already had more race wins, pole positions and podium finishes than any other driver in the history of the sport.
A decade on from their last driver's title, courtesy of Kimi Raikkonen in 2007, Ferrari emerged from eight days of testing in Spain with the fastest lap times coupled with impressive reliability.
Ferrari showed off their 2020 Formula One car with a theatrical show of pride and passion on Tuesday, assuring success-starved fans that it was also very different under the skin to last year's model. The SF1000, marking the Italian team's 1,000th race that comes up this year, is the car Ferrari hope can end six years of Mercedes domination and dash Lewis Hamilton's bid to equal Michael Schumacher's record seven titles.
The Ferrari driver's best time of one minute 16.231 seconds was close to the 2018 Spanish Grand Prix pole time by Lewis Hamilton for Mercedes.
Red Bull's Mexican Sergio Perez was a distant third, struggling with dehydration after a water bottle failure in the Texas heat.
Three-time world champion Lewis Hamilton, who incurred a penalty that ensured he finished second behind Ferrari's Sebastian Vettel at the Bahrain Grand Prix, has issued an apology to his Mercedes team.
Team-by-team prospects for the Formula One season starting in Melbourne, Australia, on March 17
Since its inaugural race in 2008 the Singapore Grand Prix has gained a reputation for being the toughest challenge in Formula One, providing drivers with an extreme test of endurance in the trickiest conditions.
Team by team analysis of Sunday's Russian Grand Prix (listed in championship order):
Charles Leclerc seized pole position for the Belgian Formula One Grand Prix on Saturday ahead of team mate Sebastian Vettel who completed a front row lockout for Ferrari.
Mercedes won the Formula One constructors' title for the fourth year in a row on Sunday but Lewis Hamilton was made to wait despite cruising to a U.S. Grand Prix victory at one of his favourite circuits.
'It's been ultimately a really great race between two different teams and it ends with a bit of a ... negative. It does kind of feel like a deflated win'
Red Bull and Renault will be working flat out to ensure Formula One championship leader Sebastian Vettel does not go into next weekend's title showdown in Brazil with a 'ticking time bomb' deep inside his car.
Team by team analysis of Sunday's Bahrain Formula One Grand Prix on Sunday.
Ferrari's Fernando Alonso was unshaken in his belief that he can win this season's Formula One title despite rival Sebastian Vettel taking another dominant pole position at the Indian Grand Prix on Saturday.
Valtteri Bottas won a dramatic first race of the delayed Formula One season for champions Mercedes in Austria on Sunday
Singapore Grand Prix promoters have ruled out holding their Formula One race without spectators, casting further uncertainty over the likelihood of the September event going ahead. Formula One plans to start its stalled season in July with races behind closed doors in Austria and Britain due to the coronavirus pandemic.
Lewis Hamilton took a huge stride towards a fourth Formula One title on Sunday with victory in an incident-packed Singapore Grand Prix after Ferrari title rival Sebastian Vettel crashed out at the start.
Winner of two Formula One championships in Brazil, Ferrari's Fernando Alonso says he feels less pressure and has nothing to lose as he chases another in Sunday's title-decider at Interlagos.
'Just the fact that people have mentioned it, it's already an honour, but it's not been something that I've been chasing in my life'
Vettel went from starting in the pit lane, after being punished for a fuel regulations breach, to the podium and also set the fastest lap.
A summary of sports events and sports persons, who made news on Monday
Lewis Hamilton won in Sunday's Azerbaijan Grand Prix ahead of Kimi Raikkonen and took championship lead.
The Briton's fourth victory in five races suggests that once again the 33-year-old is hitting a purple phase just as the season enters its critical stages.
Six time world champion Lewis Hamilton, winner of the British Grand Prix from pole position at the same circuit last weekend and 30 points clear of Valtteri Bottas after four races without spectators, was 0.138 seconds slower.
Ferrari are closer to Mercedes than results have suggested in this season's two races and look like posing a real challenge, according to Formula One world championship leader Nico Rosberg.
Red Bull's Max Verstappen, last year's winner at his team's home circuit, qualified third.
Hamilton's team mate Valtteri Bottas finished third, ahead of Ferrari's Charles Leclerc, in a race aimed at providing more thrills for fans over the three days of track action and potentially shaking up the starting grid.
Lewis Hamilton has raised his game but whether the Mercedes driver can deny Ferrari a second successive win of the season in China this weekend remains to be seen.
Nico Rosberg cruised to victory in the first Formula One race held in Azerbaijan on Sunday and increased his championship lead over Mercedes team mate Lewis Hamilton to 24 points. While the German enjoyed an uneventful drive in the late afternoon sunshine, triple world champion Hamilton worked up a head of steam as he wrestled with his car's settings without the team being able to help.
The 21-year-old is the first Ferrari driver since seven times champion Michael Schumacher to take four consecutive poles in a single season.