Despite the educational significance of peer feedback, previous research has mainly focused on the receiving of feedback, with less attention on the effects of the act of providing feedback itself. This study aimed to investigate the effects of peer feedback in terms of both providing and receiving feedback, considering different types of feedback and the influence of writing self-efficacy on these effects for a more nuanced discussion. A total of 123 middle school students participated in the study in which they provided and received feedback on the first draft and then revised their writing accordingly. Peer feedback was coded based on the criteria established in previous research. Relationships between variables were analyzed using a multiple multivariate regression analysis. Results revealed that, unlike receiving feedback, certain types of feedback had significant effects on revised writing when given by peers. The participants’ awareness of feedback activities was evident for some types of feedback in both the providing and receiving dimensions.