Objective: The present study examined variations in the degree of smartphone use behavior among male and female adolescents as well as the association between various degrees of smartphone use behavior and the vitality and mental health of each gender. Participants: A total of 218 adolescents were recruited from a junior college in September 2014. Methods: All the participants were asked to answer questionnaires on smartphone use. Results: The findings showed that adolescent females as compared with adolescent males exhibited significantly higher degrees of smartphone dependence and smartphone influence. Positive correlations were observed between the duration of smartphone use on weekends and the vitality/mental health of the male adolescents; negative correlations were found between smartphone dependence and the vitality/mental health of males. Conclusion: The findings demonstrate that adolescent females are deeply affected by their smartphone use. Smartphone dependence may decrease the vitality and mental health of male adolescents.