Problematic smartphone use (PSU) leads individuals to spend excessive amounts of time on their smartphones, indicating a distortion in their perception of time. The current cross-sectional study aimed to analyze loneliness and the fear of missing out as potential mediators between PSU and time distortion. We recruited 893 Chinese undergraduate students (586 females) through cluster sampling via a web-based survey that assessed loneliness, fear of missing out, anxiety and depression, PSU, impulsivity, craving for addictive stimuli, and time distortion. Cravings triggered by addictive stimuli are not significantly associated with time distortion in PSU. A significant negative association was found between the severity of PSU and time distortion (r = -0.075, p < 0.05) after controlling for participants' levels of impulsivity. In the final model, PSU was negatively related to time distortion indirectly through the mediating effects of loneliness and fear of missing out. After accounting for an individual's level of impulsivity, PSU, fear of missing out, and loneliness were found to be closely related. This indicates the significant impact of PSU on individual time distortion. Reducing the level of loneliness and fear of missing out among PSU has a certain effect on improving their time distortion.