The purpose of the present study was to examine the moderating role of child-teacher relationship quality (i.e., closeness, conflict, and dependence) in the association between children's shyness and indices of socio-emotional adjustment and maladjustment. The participants were Italian preschool children (63 boys; 66 girls) and two lead teachers per classroom (N?=?7 classrooms). In each classroom, one teacher, randomly selected, evaluated the quality of the child-teacher relationship; the other evaluated children's social competence and maladjustment. Peer liking was measured using a sociometric procedure. Parents provided an assessment of their children's shyness. Shyness was positively related to teacher-reported rejection and internalizing problems whereas shyness was negatively associated with closeness and conflict with teachers. Moreover, closeness, conflict, and dependence in the child-teacher relationship moderated the links between children shyness and indices of preschool social competence and maladjustment. For example, among children with low levels of closeness, shyness was negatively associated with teacher-reported social competence and positively related to teacher-reported peer rejection. At very high levels of dependence, there was a negative relation between shyness and social competence. The findings suggest that a positive child-teacher relationship may be a protective factor in avoiding social maladjustment in Italian "scuole d'infanzia," where most pupils remain with the same teacher for 3?years.