BACKGROUND: Screen time encompasses activities conducted on digital devices, including traditional devices such as televisions and computers, as well as modern devices like smartphones, tablets, and other digital screens. Excessive screen time among children has been linked to a heightened likelihood of engaging in high-risk problem behaviours. This study aimed to quantify the prevalence of excessive screen time and delve into its correlation with problem behaviours among school-aged children in Fujian, thereby gaining insight into the prevalence and trends within this region. METHODS: From October to November 2022, we used cluster sampling and invited 891 school-age children from Fujian as participants. Parents recorded children's screen time for a week, taking the average value of seven days, and the unit is minutes. The Child Behaviour Checklist was used to assess their problem behaviours. Correlation analysis, Propensity Score Matching, Single-factor analysis, and Multi-factor analysis were used to explore the influencing factors and correlation. RESULTS: Screen exposure time of school-age children was 34.29 (17.14, 55.71) min/day. Then, 17.06% were exposed to excessive video. The total CBCL score of school-age children was 10.00 (3.00, 22.00), and 10.00% had problem behaviours. After matching the propensity score, the total score of problem behaviours in the daily over-exposure group was higher than that in the non-over-exposure group (Z = 5.466, p <
0.001). Generalized linear model analysis showed that after controlling confounding variables, daily video exposure time or daily excessive screening could affect problem behaviours (p <
0.05). CONCLUSIONS: The incidence of problem behaviours among school-age children is low in Fujina. The daily screen time, weekday screen time, and weekend screen time were positively associated with problem behaviours. We suggested family members shift to more serious and cautious attitudes toward children's screen exposure and adopt appropriate digital-related parenting practices, such as accompanying children when they inevitably need to watch electronic devices, to better understand and manage their screen time.