Smartphone has been widely used by the younger generation. However, research exploring the "technostress" triggered by smartphone use lacks. Based upon the stressor-strain-outcome model, this study examined how smartphone use, especially "compulsive use," "life invasion," and "information overload," cause university students' "technostress" and, furthermore, how "technostress" impact their "sleep quality" and "academic performance." Data were collected from 540 undergraduates studying at a Chinese public university and analyzed using structural equation modeling. Results revealed that "compulsive smartphone use" and "information overload" are both positively associated with "technostress," which in turn have a positive effect on "poor sleep quality" and "academic self-perception." Furthermore, "compulsive smartphone use" indirectly predicts sleep and academic problems through the mediating effect of "technostress." The findings contribute to extend the existing "technostress" literature and provide valuable practical implications for smartphone-related designers, university teachers, and students.