The Appropriate Pain Behavior Questionnaire (APBQ) was employed to examine the effects of the participants' sex and culture on their beliefs regarding gender-appropriate pain behavior. The APBQ examines beliefs about the social acceptability to male and female participants of the behavioral and verbal expressions of pain by men and women (referents) in the presence of others [Nayak, S., 2000. Cross Cult Research 34, 135-151]. The participants were 18 male and 14 female Japanese, and 11 male and 21 female Euro-Americans. There was a significant effect of sex: female participants considered pain behaviors more acceptable than male participants. There was a significant effect of culture: compared to both male and female Japanese, Euro-American participants rated pain behaviors in both sexes to be more acceptable. There was also a significant effect of referent gender: for both sexes in both cultures, pain behaviors in women were rated as more acceptable than in men. Furthermore, a significant interaction was found between referent gender and sex of the participant: Male and female participants of both cultures were equally accepting of pain behaviors in women, but male participants were less accepting of pain behaviors in men than in women. There also was a significant interaction between referent gender and culture of the participant: Japanese participants considered pain behavior in both genders to be less acceptable than did Americans. The results are explained in terms of cultural traditions and social roles, and have clear implications for clinical treatment and diagnosis.