The fight will serve as the main event that takes place at the Mohegan Sun in Uncasville, Connecticut, which has been the promotion's unofficial home during the pandemic.
Macfarlane, 30, is 10-0 in Bellator. She most recently defeated Kate Jackson via unanimous decision on Dec. 19. Meanwhile, Velasquez, 34, is 5-0 in Bellator and last won via unanimous decision against Bruna Allen on the same card.
Macfarlane is considered one of the faces of Bellator and one of the best female fighters in the world.