The rapid development of the coronavirus disease 2019 (COVID-19) outbreak has brought great harm to physical and mental health of the public. This study aims to investigate the psychological status and sleep quality of the Chinese public during the outbreak of the COVID-19 and its related factors. The survey was conducted from February 17th to February 26th, 2020 in southwestern China. The snowball sampling method was used to invite subjects. Demographic data were collected, and mental status and sleep quality were assessed by the Generalized Anxiety Disorder-7 Scale (GAD-7), the Patient Health Questionnaire-9 (PHQ-9), and the Pittsburgh Sleep Quality Index (PSQI). Descriptive, univariate, and correlation analyses were used to investigate risk factors for psychological status and sleep patterns. A total of 1509 adults (713 males and 796 females) were enrolled in this study. The overall prevalence of anxiety, depression, and decreased sleep quality were 22.3%, 32.2% and 35.4%, respectively. Compared with females, male population has witnessed a higher prevalence of anxiety symptoms (25.1% vs 20.4%, P= 0.007) and depressive symptoms (34.6% vs 30.0%, P= 0.027). In addition, age, marital status, living situation, involvement in anti-pandemic work, basic health status and work status were significant risk factors for anxiety or depression (P< 0.05). During the COVID-19 outbreak, psychological problems and sleep disorders were prevalent among the Chinese public. More attention should be paid to males, the elderly, the solitary, the unemployed, front-line workers in pandemic prevention, and patients with chronic diseases. [ABSTRACT FROM AUTHOR]