Peer assessment has proven to have positive learning outcomes. Importantly, peer assessment is a social process and some claim that the use of anonymity might have advantages. However, the findings have not always been in the same direction. Our aims were: (a) to review the effects of using anonymity in peer assessment on performance, peer feedback content, peer grading accuracy, social effects and students' perspective on peer assessment; and (b) to investigate the effects of four moderating variables (educational level, peer grading, assessment aids, direction of anonymity) in relation to anonymity. A literature search was conducted including five different terms related to peer assessment (e.g., peer feedback) and anonymity. Fourteen studies that used a control group or a within group design were found. The narrative review revealed that anonymous peer assessment seems to provide advantages for students' perceptions about the learning value of peer assessment, delivering more critical peer feedback, increased self-perceived social effects, a slight tendency for more performance, especially in higher education and with less peer assessment aids. Some conclusions are that: (a) when implementing anonymity in peer assessment the instructional context and goals need to be considered, (b) existent empirical research is still limited, and (c) future research should employ stronger and more complex research designs.