The Briton dominated at Suzuka after starting on pole, stretching his lead over Ferrari's Sebastian Vettel to 67 points with just four races left as the German's hopes were dashed by a collision with Red Bull's Max Verstappen, AFP reported.
Valtteri Bottas held off Verstappen to take second almost 13 seconds behind Hamilton in a breathless 53-lap race at the fast-flowing Japanese circuit.
"Woo-hoo! I love you guys!" Hamilton screamed over team radio after his sixth win in the last seven races.
"I hope you guys are not getting bored of this – because I'm definitely not."
Vettel realistically needed to win to keep alive his fading title hopes but, despite making up four places in a frantic start after starting on the fourth row, spun off on lap eight in a shower of sparks after a risky lunge on Verstappen.
The German, who began from eighth in qualifying, survived the scrape but found himself back in 19th and could only finish sixth, dealing a hammer blow to his slim title hopes.
Hamilton will retain his world title if he wins the next race at Austin and Vettel fails to finish second.
"It's a great one-two for Mercedes and a true showing of the strength in depth we have," said the Briton after his fifth Japan victory and ninth of the season.
"I can't wait to unleash this beast in Austin," he added, pointing at his car. "We've gone from strength to strength this year as a team but I'm taking it one step at a time."
Daniel Ricciardo finished fourth for Red Bull after starting way back in 15th with Kimi Raikkonen fifth after Ferrari opted not to switch his position with Vettel for the sake of two extra points.