Orioles manager Buck Showalter said Wolf was expected to arrive in Baltimore on Wednesday and there's a chance he could be activated before Thursday's game against the Chicago White Sox.
Wolf was cut loose by the Brewers after going 3-10 with a 5.69 ERA.
Showalter said, "He had options, and this is where he chose to come. I think he's capable of doing some good things for us."
Wolf won only one of his last 19 starts, but Showalter said, "Randy is a starter initially, and it's also an option for him to pitch in relief."
The Orioles have only one left-hander in the bullpen, converted starter Brian Matusz.