Review of previous research on cultural differences in pain experience and/or pain behavior revealed that cultural affiliation affects pain perception and response. Unfortunately, the many inconsistent findings in the literature on cultural differences in pain experience and behavior have made interpretations and comparisons of results problematic. These inconsistent findings could be attributed to variations in acculturation level among cultural groups. The purpose of this study was to investigate cultural differences in pain experience (assessed by McGill Pain Questionnaire, the Box Scale, the Headache Pain Drawing, and the Headache Questionnaire) and pain behavior (measured by determining medication use and interference of daily functioning due to headaches) among Mexican (n = 43), Mexican American (n = 36), and Anglo American (n = 50) female chronic headache pain sufferers. The contribution of acculturation to differences in pain experience and behavior among cultural groups was measured by the Acculturation Rating Scale for Mexican Americans. The three cultural groups of women significantly differed on pain experience and pain behavior. Specifically, Mexican women experienced their headache pain more intensely, severely, and emotionally than Mexican American and Anglo American women. Furthermore, Mexican women were more willing to verbally express their pain than the other two groups. As for pain behavior, Mexican women took more medication and reported more severe inhibition of daily activities due to headaches than Mexican American and Anglo American women. Ethnic identity, ethnic pride, and language preference were factors in the acculturation process which contributed the most to women's chronic pain experience and behavior. The greatest variability occurred within the Mexican American group of women who perceived themselves as being more Mexican in attitudes and/or behaviors, but more similar to Anglo American in their pain experience and pain behavior. Results are explained using biocultural multidimensional pain theory, social learning theory, and acculturation theory.