<p>Fear of missing out (FoMO) has become a common emotion that has a strong relation with mental health, while their covariation remains unclear. The study aimed to investigate the covariation between FoMO and mental health and to identify the dimension of mental health (including depression, anxiety and stress) most relevant to FoMO. A total of 542 college students (<i>M</i>_age = 19.72 ± 2.28 years old) participated in the three-wave assessment study, spaced over a two-week period. They were required to complete the Fear of Missing Out Scale (FoMOs), the Depression Anxiety Stress Scale-21 (DASS-21), and the background questionnaire. Parallel-process latent growth curve models were used to explore the covariation between FoMO and mental health (including depression, anxiety and stress). The results showed that the FoMO intercept was positively correlated with the intercepts of mental health and its three dimensions. The slope of FoMO was positively associated with the slopes of mental health and the stress dimension. The intercept of FoMO negatively predicted the slopes of mental health and the stress dimension. In conclusion, the study highlights that FoMO covaries with mental health, especially with the stress dimension. Further interventions could focus on reducing FoMO and stress. This might decrease the risk of depression and anxiety, thereby improving mental health.</p>