Objective To explore the loneliness and its influencing factors in naval officers and soldiers. Methods With simple cluster sampling, the University of California at Los Angeles (UCLA) loneliness scale, perceived social support scale, interpersonal comprehensive diagnostic scale, self-esteem scale, general self-efficacy scale, general anxiety disorder scale 7, patient health questionnaire scale 9 and self-designed demography questionnaire were used to investigate the officers and soldiers in Apr. 2022. Correlations between general demographic variables and psychological variables were analyzed by Spearman correlation analysis and Pearson correlation analysis. Simple linear regression analysis and multiple linear regression analysis were used to explore the relationships between social support, interpersonal relationship, self-esteem, self-efficacy, anxiety, depression and loneliness. Results A total of 3 338 questionnaires were distributed and 3 105 valid questionnaires were collected, with an effective rate of 93.02%. Among the survey subjects, 3 032 (97.65%) were male and 73 (2.35%) were female, aged 18-55 (25.85±5.30) years old. The loneliness score of the officers and soldiers was 20-69 (34.04±9.79). There were significant differences in loneliness in different gender and age groups (bothP＜0.05), among which loneliness of the females was significantly higher than that of the males and loneliness of those aged 26-33 was significantly higher than that of those aged 18-25 (both P＜0.05). The loneliness of officers and soldiers was positively correlated with interpersonal relationship score and anxiety and depression levels (all P＜0.01), and was negatively correlated with perceived social support, self-esteem and self-efficacy (all P＜0.01). Interpersonal relationship score and anxiety and depression levels had significant positive predictive effects on loneliness (all P＜0.01), while the levels of perceived social support, self-esteem and self-efficacy had significant negative predictive effects on loneliness (all P＜0.01). Conclusion Social support, interpersonal relationship, self-esteem, self-efficacy, anxiety and depression have significant impacts on loneliness in naval officers and soldiers.