Sleep deprivation can cause serious physical and mental problems. Although sleep deprivation among adolescents is not a new phenomenon, this problem has recently gained more attention due to the frequent use of smartphones. This study aimed to explain the correlations among family support, academic stress, social network site (SNS) use, and insomnia in adolescents. This cross-sectional study included 180 adolescents aged 16 to 17 years, with simple random sampling. This study used a questionnaire that included the frequency and duration of social media use, reasons for using social media, family support, academic stress, and insomnia. Data were analyzed using multiple logistic regression with a degree of significance at P < 0.05. This study showed that insomnia was associated with duration of SNS use (P = 0.011), reasons of SNS usage ( P = 0.004), and academic stress ( P = 0.013). The frequency of SNS use ( P = 0.645), types of SNS ( P = 0.965), and family support ( P = 0.150) were not associated with insomnia in adolescents. The reasons of SNS usage, duration of SNS usage, and academic stress are major factors associated with insomnia in adolescents. These components should be embedded in multicomponent educational intervention addressed to both adolescents and parents to reduce insomnia.