The role of fear of missing out (FoMO) in addictive behaviors has recently attracted growing attention. In view of negative effects of gaming disorder (GD) among adolescents and emerging adults, research examining the relationship between FoMO and GD is needed, alongside the roles of impulsivity and gender in the relationship between FoMO and GD. This study examined whether impulsivity as a mediator and gender as a moderator impacted on the relationship between FoMO and GD among a sample of Chinese university students. A sample of 1,288 Chinese university students from three universities completed an online survey through the Wenjuanxing platform. The Chinese Trait-State Fear of Missing Out Scale, the Barratt Impulsiveness Scale-Brief, and the Chinese Gaming Disorder Scale were used in this study. The model results indicated that impulsivity partially mediated the relationship between FoMO and GD, and that there was a larger effect size between impulsivity and GD among males. High levels of FoMO among individuals may impact on executive functions leading to more impulsivity, and are associated with GD. Gender may moderate the relationship between impulsivity and GD. This study deepens the understanding of the relationship between FoMO and GD, and provides new perspectives for practitioners to incorporate into health prevention programs to help regulate emotion, control impulsivity, and decrease GD.