The Goodness-of-Fit model [Thomas, A., & Chess, S. (1977). Temperament and development. New York: Brunner/Mazel] proposes that a child's temperament interacts with the environment to influence child outcomes. In the past, researchers have shown how the association between the quality of the teacher-child relationship in daycare and child behaviour is moderated by temperament [Vitiello, V., Moas, O., Henderson, H., Greenfield, D., & Munis, P. (2012). Goodness of fit between children and classrooms: Effects of child temperament and preschool classroom quality on achievement trajectories. Early Education and Development, 23, 302-322.]. Our goal was to examine how teacher-child relationship quality is associated with prosocial behaviour in preschool children and the moderating role of temperament. Information about 60 children (n = 60) in preschool daycare within Eastern Canada was provided by daycare teachers. Children were classified into temperament categories (undercontrolled, overcontrolled, and resilient) and rated on prosocial behaviour. Results revealed that temperament significantly moderates the association between teacher-child relationship and prosocial behaviour. Goodness of fit was supported, in that having a good fit between teacher-child relationship and temperament was predictive of increased prosocial behaviour. Relevance to goodness of fit is further discussed with relation to previous research. (author abstract)