Abstract In order to investigate the role of aluminum nitride (AlN) in corrosion behavior of Al/AlNp composites, metal matrix composites based on pure aluminum reinforced with AlN particles was prepared. The corrosion behavior of Al/AlNp composites was examined by various techniques. It has been found that there is the micro-galvanic action between hydrolyzed AlN particles and the matrix Al, which results in the increased susceptibility to pitting attack for Al/AlNp composites. The micro-galvanic corrosion is attributed to hydrolysis of AlN particles.