Mack, 28, inked a one-year contract.
Financial terms were not disclosed.
"We are very happy with the improvement we made to our offence with the addition of Stacey Mack," Texans general manager Charley Casserly said.
Mack gained 436 yards on 98 carries with nine touchdowns in 16 games for the Jacksonville Jaguars last season.
The 6-foot-1, 238-pound Temple product also caught 11 passes for 79 yards.
"Stacey is a powerful running back who has a good chance to make an impact on our rushing game," Casserly said.
Mack has rushed 372 times for 1,498 yards and 19 TDs in 50 NFL games, including 13 starts.
He joined Jacksonville as an undrafted rookie in 1999.
with files from Sports Network
