PurposeThis study aims to reveal the effect of comment interactions on video engagement of users in video-sharing platforms.Design/methodology/approachThe authors collected 87,232 comments on 647 videos of Korean beauty creators on YouTube and conducted a social network analysis and a hierarchical regression analysis.FindingsThe results present that the more evenly interactive participants write and receive replies in the comments section, the more users' video engagement increases. The more creators reply to user comments and the more reactions they present, the more video engagement increases. Additionally, the influence of the creator's interaction on user engagement increased as the number of commenting participants decreased.Practical implicationsThis study has implications for platform operators regarding comment section design and proposes interaction strategies for content creators to induce users' video engagement.Originality/valueCompared to previous studies, this study empirically verifies the influence of interactions on video-sharing platforms in detail by confirming the influence of user interaction structures and creator's participation in the interaction on video engagement.