Hispanic problem behavior youth are at an increased risk of engaging in HIV risk behaviors, including low condom use. However, relatively little research has examined factors that affect condom use in this population. Although research indicates that family processes, such as higher levels of family functioning and open parent-adolescent communication about sex, and condom use attitudes, norms, and control beliefs as depicted by the theory of planned behavior have an effect on condom use behaviors, the combination of the two factors has received minimal attention. The purpose of this study was to examine the effect of family functioning on condom use intentions and behaviors through communication about sex and condom use attitudes, parental norms, and control beliefs. A cross-sectional study of 171 predominately male (73.1%) sexually active Hispanic problem behavior adolescents (mean age = 14.88 years) was conducted. Structural equation modeling was used to test the study hypothesis. Findings largely support the overall model and suggest that family functioning had an indirect effect on condom use intention and behavior through communication about sex, condom use attitudes, and control beliefs. Family functioning, however, did not have an indirect effect on condom use intention and behavior through communication about sex and parental norms. Implications for prevention science and future research are discussed. (Contains 1 table and 1 figure.)