Objective To analyze the risk factors of pessimistic ideation of military officers and soldiers. Methods With cluster sampling, 432 military officers and soldiers were selected. Self-designed general information questionnaire was compiled to collect the age, gender, residence, parental relationship, family economic condition and marital status. Patient health questionnaire (PHQ-9), generalized anxiety disorder scale (GAD-7), insomnia severity index (ISI), satisfaction with life scale (SWLS) and mental health continuum-short form (MHC-SF) were used to investigate the depression, anxiety, subjective sleep quality, life satisfaction and well-being. Pessimistic ideation was measured by the 9th item of PHQ-9, and the relationship between pessimistic ideation and the above factors was analyzed. Results Depression (r_s=0.285, P<0.01), anxiety (r_s=0.245, P<0.01), subjective sleep quality (r_s=0.117, P=0.016), life satisfaction (r_s=-0.181, P<0.01) and well-being (r_s=-0.241, P<0.01) were correlated with pessimistic ideation. The logistic regression model included 2 effective factors:depression (P=0.017) and well-being (P=0.029). Well-being had a complete mediating effect between subjective sleep quality and pessimistic ideation, accounting for 66.37% of the total effect. Conclusion The higher the degree of depression and the lower the sense of well-being, the higher the possibility of pessimistic ideation. Poor subjective sleep quality may reduce well-being and increase the risk of pessimistic ideation among military officers and soldiers.