The 22-year-old 7-footer (2.17m) suffered the injury after playing only four minutes in Houston's 128-86 rout of the Shanghai Sharks in a pre-season exhibition contest Tuesday night.
Zhou, who played 18 games for the Rockets last season, was hurt during an awkward scramble for a loose ball in what was supposed to be a game where he could shine against a club from him homeland.
Instead, the night ended early when Zhou's left leg was pinned under Shanghai's Luis Scola, a former Rocket.
Zhou, who pulled down two rebounds in the contest before leaving, stayed on the floor several minutes and was taken off the court in a wheelchair to the locker room.
Zhou, a second-round pick taken 43rd overall in the 2016 NBA Draft, averaged 1.2 points and 1.2 rebounds a game last season for the Rockets.
"Zhou Qi has shown some good stuff," Rockets coach Mike D'Antoni said.
Zhou spent three seasons in China with the Xinjiang Flying Tigers, helping them capture the Chinese crown in 2017.