The present research examined the possibility that mild task conflict and relationship conflict can serve as antecedents of psychological safety climate of newly formed teams and in turn influence team effectiveness in creative performance. Specifically, we suggest that mild task conflict is positively related to psychological safety, while relationship conflict is negatively related. Furthermore, psychological safety would mediate the relationships of mild task conflict and relationship conflict to creative team performance and team attachment. This proposed model was tested using a sample of 194 participants in a total of 35 teams surveyed at 2 time periods over about 4 months. The data analysis provides evidence to support our proposed model. The results indicate that mild task conflict and relationship conflict are critical team processes to influence emergence of team psychological safety climate which promotes team effectiveness in creative task performance. Finally, theoretical and practical implications, limitation and suggestion for future research are discussed.