Harden hit a leaning 3-pointer with 1:05 remaining to get to 30 points for the 25th consecutive game, tied for the third-longest such streak in NBA history with Wilt Chamberlain, who is the only player to surpass it.
However, Harden didn't finish as the game's leading scorer for the first time since a Dec. 11 loss in Portland, a 24-game streak that ranks behind only Chamberlain's run of 40 straight games as the leading scorer in 1961-62, according to ESPN Stats & Information.
Denver shooting guardMalik Beasley scored a career-high 35 points, and All-Star center Nikola Jokic had 31 to help the Nuggets snap a nine-game losing streak against the Rockets.
"We've beaten all comers. We're not scared of anybody," Denver coach Michael Malone said. "If we play them in the playoffs, now we know we've beaten this team. We know what it takes to beat them."
Jokic, who also had 13 rebounds and nine assists, dominated a Houston team forced to play small with center Clint Capela recovering from right thumb surgery. He repeatedly bullied Rockets defenders on post-ups, making 12 of his 15 shots from the floor.
The Nuggets are getting accustomed to those kinds of performances from Jokic, who received "MVP! MVP!" chants on several occasions throughout the game. Beasley's breakout performance as a fill-in starter provided a massive lift for the Nuggets with guards Gary Harris (adductor) and Jamal Murray (ankle) sidelined.
"I definitely think this is a statement performance to show the world who I am," Beasley told ESPN. "I'm not just out there on the bench. I'm not just on this team with a lot of great players. I am a player. I work hard just like everybody else.
"I'm glad I got to show it tonight, and most importantly, it was a great team win."
Beasley had 22 points -- one shy of his previous career high -- by halftime to help the Nuggets score 83, tied for the second most by any team in a first half this season. He had 14 points on 4-of-4 shooting during Denver's 48-point second quarter.
"Once you give a guy confidence like that, especially early in the game, he just carried that wave that he had," Harden said. "He got a couple of open looks and in transition was getting to the basket, got a couple of big-time dunks. You give a guy like that confidence, anything can happen."
Beasley, a 2016 first-round pick who played sparingly in his first two seasons, was 12 of 17 from the floor and 5-of-9 from 3-point range. He has established himself as a quality rotation player this season, averaging 11.2 points in efficient fashion (.501 field goal percentage, .426 3-point percentage).
"That guy is just continuing to grow up in front of all of our eyes," Malone said. "Right now, he's shooting into a big basket. He's shooting with great confidence, and he's embracing the challenge to guard every night. Hard work pays off."
Beasley also played a significant role in limiting Harden to 30 points on 9-of-21 shooting. Beasley and Torrey Craig were the primary defenders on Harden, and the Nuggets frequently trapped the reigning MVP to force the ball out of his hands.
Harden scored 15 points on 5-of-6 shooting in the first quarter but missed all but two of his 11 shots over the next two quarters as Denver built a commanding lead. He made three 3s in the fourth quarter to extend his streak of 30-point performances, but the Rockets never made a serious comeback threat against the Nuggets (36-15), who pulled even with the Golden State Warriors for the best record in the Western Conference.
"I didn't want him to get 30," said Craig, who also had a career high with 22 points, highlighted by a southpaw putback slam dunk. "I was trying real hard to stop him from getting 30, but that last shot where he leaned in at the end, he hit it. Our team was giving me a hard time about it.
"He's a great player. He's obviously one of the best scorers in the league. To hold him to 30 after the way he's been playing, and we get the win, so I'm not too disappointed."
Jokic, Beasley lead Nuggets to win vs. Rockets
Nikola Jokic nearly reaches a triple-double while Malik Beasley records a career-high 35 points as Denver beats Houston 136-122.
Harden's 30-point streak reaches 25 games
James Harden pushes to 30 points with a late 3-pointer in the loss to the Nuggets, extending his 30-point streak to 25 games.