Objective To investigate the possible role of plasma leptin and total cholesterol in the pathophysiology of attempted suicide in depressive episode patients. Methods The subjects were 25 depressive episode patients who had recently attempted suicide and 30 depressive episode patients without suicide attempt. The Hamilton Depression Rating Scale-24 items ( HAMD24 ), Beck Helpless Rating Scale (BHS) and Self-rating Idea of Suicide Scale (SIOSS) were used to evaluate the severity of symptoms. In addition, 32 individuals who took part in health examination were selected as health control group. Body height and weight were measured to get body mass index (BMI) of all objects, and plasma leptin and total cholesterol were measured by venous blood before taking pill. Results (1)HAMD score , BHS score and SIOSS score in patients with attempted suicide were higher than patients without suicide (P ＜ 0.01 ). (2) The total cholesterol and plasma leptin in patients with attempted suicide ( (3.3 ±0.9)mmol/L, (6.1 ±3.7)μg/L)were lower than that in patients without suicide( (3.6± 1.2)mmol/L, (9.4 ± 4.4)μg/L; P ＜ 0.05 ～ 0. 0l ), while total cholesterol and leptin in patients without suicide attempt ( (3.6 ± 1.2 ) mmol/L, ( 9.4 ± 4.4 ) μg/L) were lower than that in normal controls ( ( 4.8 ± 0.9 )mmol/L, ( 13.4 ± 6.7 ) μg/L; P ＜ 0.05 ～ 0.01 ). (3) Plasma leptin and total cholesterol of all patients were positively correlated with BMI(P＜0.01 ). Moreover, plasma leptin and total cholesterol in patients with attempted suicide and patients without attempted suicide were inversely positively correlated with HAMD score , BHS score and SIOSS score. Plasma leptin was significantly positively correlated with total cholesterol in patients with attempted suicide and patients without suicide, but there was no significant difference in normal controls(P＞ 0. 05). Conclusion The results suggest that decreased plasma leptin is related to the pathophysiology of attempted suicide in depressive episode patients.