Abstract： Objective To analyze the influencing factors of sertraline and its combined calibration concentration.Methods A prospective study method was used to select 80 psychiatric patients treated with sertraline in the hospital from January 2022 to January 2023.Questionnaire survey was used to investigate the gender,age(≤14 years old,15-18 years old,19-60 years old,≥61 years old),body mass index(BMI)[low weight,normal,overweight and obese],frequency of administration(once/d,twice/d),combined administration(quetiapine,olanzapine,valproate,lithium salt)and other basic information of the patients.After ensuring that the patients had reached at least 5 half-lives,3 mL of peripheral venous blood was collected from the patients for 2 hours in the morning after oral administration of sertraline,and the serum concentration of sertraline and corrected concentration were detected by liquid chromatography tandem mass spectrometry.Results The average dose of sertraline in 80 patients was(153.02±12.22)mg/d,the average blood concentration of sertraline was(85.02±13.07)ng/mL,and the corrected concentration of sertraline was(0.68±0.23)(ng·mL-1·mg-1)·d.Except for gender and BMI,there were statistically significant differences(all P<0.05)in age,frequency of administration,dosage of combination therapy,and average blood concentration of sertraline.The differences in gender,age,BMI,administration frequency,and corrected concentration of combination therapy were statistically significant(all P<0.05).The results of regression analysis showed that the frequency of administration and combination therapy had statistical significance(P<0.05)in the regression analysis.Conclusion The frequency of administration and combination therapy can both affect the blood concentration of sertraline,and the combination therapy with olanzapine or lithium salt can adjust the dosage of sertraline.