Adolescents' problematic behavior is in relation to premarital sexual behavior. Adolescents' premarital sexual behavior can cause abortion, unwanted pregnancy, death, potential HIV/AIDS infection as well as moral decency crime in Gowa District. Factors of premarital sexual behavior among adolescents include gender, origin of school, status and frequency of dating, religious norms, household norms, knowledge and the uses of smartphone. This research aims at analyzing adolescents' characteristics of and the uses of smartphone in relation with premarital sexual behavior among high school students in Gowa District, South Sulawesi Province. It was the correlational design quantitative research. Total samples amounted to 500 high school students in Gowa District, South Sulawesi Province after these were selected with the cluster sampling. The questionnaire used in this research consisted of religious norms (the reliability test results of 0.791, R-value of 0.397-0.678), household norms (the reliability test results of 0.856, R-value of 0.430-0.893), knowledge (the reliability test results of 0.738, R-value of 0.362-0.514), and premarital sexual behavior (the reliability test results of 0.844, R-value of 0,483-0,763), smartphone use with the calculated R value > r table (0.514) the reliability indicates the alpha cronbach's value> 0.60. The analyzed data use Chi square and logistic regression. The research results show that the premarital sexual behavior has total risk value of 66.0% and the unrisky value of 34.0%. It relates to some adolescents' characteristics among others frequency of dating (p=0.000), status of dating (p=0.000), religious norms (p=0.000), household norms (p=0.000), knowledge (p=0.000), and smartphone use (p=0.000), the variables of adolescents' characteristics i.e. gender and the origin of school do not have significant relationship (p> 0.05). The smartphone use is the most significant factor with the premarital sexual behavior (OR=3.583). The smartphone use is the most significant factor with premarital sexual behavior, and therefore, it indicates that teachers at school and parents at home should who carry out the control and adolescent education in the smartphone use are important factors to be upgraded. The school based health education program can avoid the risky premarital sexual behavior, and the program can focus on the control of smartphone use and skill training among adolescents.