The maternal behavior of an abusive Japanese macaque multiparous female was compared with that of three primiparous normal females from the same colony to evaluate the quality of the abusive mother-infant relationship. The abusive mother-infant pair scored highest on maternal warmth, protectiveness, possessiveness, and scored lowest on maternal rejectingness. The finding that the abusive mother alternated violent abuse with attentive maternal care is not consistent with the learning defect explanation of monkey infant abuse. Rather, the intense anxiety she showed in the relationship with her infant indicates that she suffered from an emotional disorder that can be adequately described by referring to Bowlby's model of anxious attachment. The implications of this case for the development of a nonhuman primate model of child abuse are examined in the light of human data clearly showing attachment disturbances in some child-abusing mothers.