Objective:To explore the association between glutamyl transpeptidase (GGT) trajectories and new-onset metabolic syndrome to provide insights for the prevention and treatment of metabolic syndrome.Methods:A total of 3 209 subjects who met the inclusion criteria were enrolled in the study cohort of physical examination population. The GGT levels before follow-up were classified by R LCTMtools program into 3 GGT trajectory groups: low-stable group, medium-stable group and high-stable group. Cox proportional hazards regression model was used to analyze the correlation between different GGT trajectories and new-onset metabolic syndrome.Results:At the end of follow-up in 2020, the cumulative incidence of metabolic syndrome was 7.0%, and the incidence of metabolic syndrome in the low-stable group, medium-stable group and high-stable group were 3.9%, 11.4%, and 15.0%, respectively, showing a growth trend ( P<0.001). After adjusting for multiple confounding factors by Cox proportional hazards regression model, the risk of metabolic syndrome in medium-stable group and high-stable group increased in the total population. The hazard ratios (95% CI)for the high stable group in males and the medium-stable group in females were 1.67(1.07-2.60) and 3.29(1.14-9.53), respectively, compared with their respective low-stable group. Conclusion:Elevated longitudinal trajectory of GGT is a risk factor for new-onset metabolic syndrome, the risk of metabolic syndrome in the total population increased with the increase of long-term GGT level. It is recommended to maintain the long-term level of GGT at about 28 U/L in males and 14 U/L in females, respectively, to achieve the goal of early prevention of metabolic syndrome.