Early social experience is critical for development of social and emotional functions, and deprivation of early social experience induces social and emotional dysfunctions in rodents and human. Recently, the orbitofrontal cortex (OFC) and amygdala have been highlighted as key brain strictures for social and emotional functions. Because prefrontal-amygdala synaptic function develops during adolescence, adolescent social deprivation may cause social and emotional abnormalities though OFC-amygdala disruption. In this study, we examined effects of adolescent social isolation on the OFC-basolateral amygdala (BLA) pathway in mice. First, we examined synaptic transmissions to BLA from medial or lateral subregions of the OFC (mOFC or lOFC) by optogenetic and patch-clamp methods. Interestingly, AMPA/NMDA ratio in the mOFC-BLA synapse was decreased by social isolation, while the ratio was increased in the lOFC-BLA synapse. Furthermore, optogenetic manipulation in behaving mice clarified that the mOFC-BLA and lOFC-BLA pathways regulated social and passive-coping behaviors, respectively. Our results suggested that adolescent social isolation induced distinct changes in the mOFC-BLA and lOFC-BLA synapses, and these changes separately contributed to social and emotional abnormalities.