Facing protests from animal-rights groups, Nike announced it was suspending Vick's endorsement deal without pay, as well as halting sales of Vick-related shoes and other products at its retail stores.
Reebok, the official uniform supplier of the NFL, said it would stop selling Vick's replica jersey at retail stores and through its Web site.
The moves came one day after the Atlanta Falcons quarterback pleaded not guilty to federal dog-fighting charges in Richmond, Va.
"Nike is concerned by the serious and highly disturbing allegations made against Michael Vick, and we consider any cruelty to animals inhumane and abhorrent," Nike spokesman Dean Stoyer said in a statement.
Since Vick has not been convicted of any crime, Nike left open the door to resume its business relationship with the star player if he's acquitted.
"We do believe that Michael Vick should be afforded the same due process as any citizen in the United States," according to the statement. "Therefore, we have not terminated our relationship."
Vick is barred from the Falcons' training camp while the league investigates his actions for possible violations of its new personal conduct policy.
Although Reebok does not have a business relationship with Vick, the Massachusetts-based company serves as the official supplier of apparel and equipment to all 32 NFL teams. Through that deal, it holds the coveted rights to sell jerseys at the retail level.
"We just find the allegations very upsetting and very disturbing," Reebok spokeswoman Denise Kaigler said. "While this is just the beginning of the legal process and we know that it has to have time to run its course, we felt that making this decision now was important and the right things to do."
Reebok said it also was willing to take back any unsold Vick jerseys that are returned by retail outlets.
Kaigler said she already had received numerous e-mails in support of the decision. Even though numerous NFL players have run afoul of the law, this is the first time Reebok has stopped sales of an individual jersey.
"The number of e-mails and statements we're getting from consumers was pretty telling about how disturbing people find these allegations to be," Kaigler said.