This study examines the effect of some demographic variables such as educational achievement, income, residence, profession and gender on parents' beliefs about their competence to deal with their adolescent children's behavioral problems. The adolescent behavioral problems investigated in this study include failure in school, alcoholism and addiction to drugs. A group of 350 parents of adolescent children was randomly selected from several districts in the Governorate of Muscat in the Sultanate of Oman. The researcher developed a questionnaire to measure the impact of these variables on certain behavioral problems specifically identified for the study. ANOVA was used to examine the role of socio-demographic variables in explaining parents' beliefs about their competence to prevent such problems. Results reveal a positive impact for the variables: educational achievement, occupation, family income, gender, and place of residence. To investigate the effects of these sociodemographic factors on each of the dimensions of competence, MANOVA was used. Results show that there is a direct relationship between the variable of level of income and children's failure in school, and that the variable of gender and the problem of alcoholism and drug addiction are related. Finally, the variable of place of residence is related to the problems of alcoholism, addiction to drugs and school failure. These results were discussed in light of findings of similar previous studies and within the framework of the Omani social lifestyles.