An increasing number of studies associate online media consumption with depressive symptoms in young people (10–24 years). However, the findings have been somewhat contradictory. This systematic review and meta-analysis aimed to examine whether the contradictory findings are due to inconsistency in type and/or measurement of online media. A review of six databases identified 531 studies (476 cross-sectional, 52 longitudinal, 3 studies used both designs) on the relationship between online media use and depressive symptoms in young people. The results showed a small bi-directional association between online media use and depressive symptoms. However, the association was significantly greater for studies that measured online media use with media addiction scales than as amount of time spent using online media. The effect size did not differ as a function of media type (internet, smartphone, social media or online gaming). These findings suggest that depressive symptoms are more closely tied to the subjective experience of addiction to online media use rather than the actual or perceived time spent on it. Further, depressive symptoms may be linked to factors that are common to spending time online, such as a lack of physical activity and sleep, less time with friends and family, or being a perpetrator and/or victim of cyberbullying.