Previous research has revealed that various elements of social networking sites, such as feedback received from “friends” on one’s posts as well as the degree of intensity of this feedback may impact one’s mental health. However, researchers have not yet examined the impact that the amount of feedback received or the perceived emotional tone of these “comments” has on psychological wellbeing. The current study sought to explore the impact that the number of comments individuals received on their Facebook posts and the perceived valence of these comments had on participants’ self esteem, body image, and affect. 110 undergraduates completed a survey measuring their internet usage, state self-esteem, state body image satisfaction, and affect before and after rating their Facebook comments. Specifically, they indicated the number of comments they received on their five most recent Facebook posts and rated the first ten comments for each post on a visual analogue scale from 1 = negative comment to 10 = positive comment. Participants also indicated whether or not each post included a picture of themselves. Multiple linear regression showed that the number of comments received on Facebook posts and the valence of these comments significantly impacted self-esteem after controlling for baseline self-esteem, with the number of Facebook comments received having greater predictive capacity of subsequent state self-esteem. There were no significant impacts of the procedure on participant’s affect or on state body image for the posts containing photographs. These findings demonstrate that the number and valence of comments on social networking posts influence psychological wellbeing, specifically state self-esteem.