Subthreshold depression (SubD) is generally considered present when individuals report clinically relevant depressive symptoms (i.e. sustained depressed mood or loss of interest) but fall short of the diagnostic criteria for major depressive disorder (MDD). The prevalence of SubD among youth ranged from 5% over the past year, to 29% over the two weeks before screening. A recent meta-analytic review has shown that, although the symptoms of SubD are less severe than MDD, adolescents with SubD are associated with elevated rates of psychiatric comorbidities, reduced social functioning, increased suicidality, and frequent mental health service utilization. Moreover, adolescents with SubD are approximately two times more likely than their non-depressed counterparts to develop major depression. Considering the SubD is characterized by the aberrations in affect (enhanced negative emotion and diminished positive emotion), researchers often examined SubD adolescents from the perspective of emotion regulation. Emotion regulation refers to the process that a person uses emotion regulation strategies to modify the experience and expression of emotion in order to meet the contextual demands. According to the process model of emotion regulation, emotion regulation strategies could be divided into five families of strategies: situation change, situation modification, attention deployment, cognitive change (i.e., reappraisal and rumination), and response change (i.e., suppression and expression). Specifically, reappraisal involves changing interpretation of emotional stimulus. Rumination refers to focusing one’s attention toward emotional experiences and their causes and consequences. Suppression involves inhibiting ongoing emotion-expressive behavior. Expression refers to exhibiting the outward expression of emotional states. Based on the conceptualization of these emotion regulation strategies, prior studies have investigated the relationship between specific emotion regulation strategy with depressive symptoms in adolescents. Previous results suggested that, compared to non-depressed (nonD) controls, adolescents with MDD report habitually using putatively maladaptive emotion regulation strategies (i.e., rumination) more frequently, and putatively adaptive emotion regulation strategies (i.e., reappraisal) less frequently. However, existing studies (1) mainly examined the differences in the use of emotion regulation strategies between nonD and MDD participates, neglecting the feature of SubD population. (2) predominantly focused on regulation of negative emotion, without fully considering positive emotion. To investigate the daily selection of emotion regulation strategies in adolescents with different depressive symptoms, 766 adolescents were recruited and divided into non-depressed, subthreshold depression, and depression groups by means of the Center for Epidemiologic Studies Scale-Depression (CES-D), and their usage of reappraisal, rumination, suppression, and expression was assessed using the Adolescent Daily Emotion Regulation Questionnaire (ADERQ) as well. The results showed that: (1) Compared to non-depressed group, subthreshold depression group and depression group utilize significantly less reappraisal, whereas use significantly more rumination, expressive suppression, and expressive expression. (2) The utilization of specific emotion regulation strategy was influenced by to-be-regulated emotion valence. (3) The frequency of four emotion regulation strategies of SubD participates fell in between of nonD and MDD counterparts, which indicated that the relation of emotion regulation strategy to depressive symptoms is linear. These results suggested that: (1) Overall, the depressive symptoms of adolescents was significantly negatively related to putatively adaptive emotion regulation strategies (e.g., reappraisal) while at the same time significantly positively associated with putatively maladaptive emotion regulation strategies (e.g., rumination). (2) The relationship of depressive symptoms with distinct emotion regulation strategies was modulated by to-be-regulated emotion valence. (3) Compared to nonD and MDD individuals, adolescents with SubD represent good targets for early screening and preventive interventions.