Lowrie, a five-year veteran, went to the A's along with pitcher Fernando Rodriguez for infielder Chris Carter and a pair of minor league prospects including pitcher Brad Peacock and catcher Max Stassi.
Lowrie batted .244 with 16 home runs, 18 doubles and 42 RBI in 97 games for the last-place Astros last season while dealing with wrist and hand injuries.
"You look at last year, what (Lowrie) did in Houston, he's always had good power for a guy that plays in the middle of the infield," A's General Manager Billy Beane told MLB.com. "It's just hard to find that kind of power [in a guy] that can play the middle infield."
Carter, meanwhile, compiled a .239 average with 16 homers and 39 RBI over 67 games for the American League West champion A's last season.
"This trade gives us power, pitching and catching," added Astros GM Jeff Luhnow said of Carter, Peacock and Stassi.