This research aims to determine the effect of social comparison on the self-esteem of emerging adulthood who use Instagram social media. Self-esteem is explained as a positive or negative evaluation of an individual’s self and a person’s assessment of the individua;l’s thoughts and feelings as a whole, where in this case a person’s self-esteem can be predicted from individual interactions on social media through social comparison. Social comparison is explained as a human attitude in testing one’s opinion and abilities against other people to form a personal identity where in this case the social comparison carried out as an encouragement or desire to evaluate the individual's self and is often judgmental and competitive and is carried out to understand how a person has more accomplishments than themselves. This research was carried out using quantitative methods and the results obtained were that social comparison had a quite significant influence on self esteem (r =.197, p <.001) which then explained that the higher the social comparison carried out, the lower the self esteem, owned by individuals who use Instagram social media.