The 22-year-old forward was not considered part of Ernesto Valverde’s first-team plans at Camp Nou and a host of clubs, both in La Liga and abroad, were registered with an interest in the forward during the transfer window.
Barca 5/4 to win La Liga
Ajax, Roma and Zenit were all linked with a move for the Spaniard, who scored six goals in 33 La Liga appearances while on loan at Valencia last season.
However, Alaves - who signed former Barca forward Bojan Krkic on loan from Stoke City on Thursday - have now concluded a deal on deadline day in Spain.
Munir could make his debut for Luis Zubeldia’s side when they travel to face Celta Vigo on September 10.