The current research was done to compare the efficiency of the family among successful and unsuccessful students. The statistical population of the research was high school students of Saghez. The method of the current research was causative -comparative. The research sample was 300 high school students (150 students with an average of more than 17 and students with an average of under 12) chosen through cluster sampling. Data were analyzed by using the family assessment questionnaire (FAD) and t test, multivariate regression, phi, Kendall's tau, and variance analysis. Findings, showed that there is a positive relationship with (0/001) alpha with respect to the efficiency of the family (except for the subscale of problem -solving) among successful and unsuccessful students. The relationship of each of the demographic variables (parents' education levels, educational major, and age) was a significant relationship on the effectiveness of the family. Family is a good predictor for the success of the students and one can enhance their success rate by strengthening the family effectiveness.