The 6-foot-10 Turiaf will give the Heat some depth at the center position as the post-season approaches, Riley said.
"We are very happy to be able to add an experienced veteran center at this stage of the season," he said. "Ronny's energy will be a great addition and bolster our front line."
Turiaf, originally drafted by the Los Angeles Lakers in 2005, averaged 4.2 points, 3.2 rebounds and 1.1 blocks over 64 games for the New York Knicks last season.
In the course of his 392-game career with the Lakers, Warriors, Knicks and Wizards, Turiaf has averaged 5.2 points, 3.8 rebounds and 1.4 blocks.