Harden had 26 points, 10 rebounds and 10 assists in three quarters for his second career triple-double as Houston picked up its fifth consecutive victory.
The 76ers (15-57) stuck around early before a big second-quarter run allowed the Rockets to pull away and roll to the win.
Philadelphia matched the 2010-11
James Anderson led the 76ers with 30 points. He made six three-pointers.
Portland 100, at Atlanta 85:
Damian Lillard added 21 points for the Trail Blazers, who had lost seven of 10 and were in danger of falling out of the fifth spot in the Western Conference playoff standings.