Objective: To evaluate the mental health status of hospitalized patients with coronavirus disease 2019 (COVID-19) and to explore the related factors. Method: This was a cross-sectional survey among COVID-19 inpatients in two isolation wards of a designated hospital in Wuhan, China, from March 7, 2020, to March 24, 2020. Participants' demographic data, clinical data and levels of circulating inflammatory markers were collated. Mental health symptoms were evaluated with questionnaires, which included the Insomnia Severity Index (ISI) scale, the 9-item Patient Health Questionnaire (PHQ-9), the 7-item Generalized Anxiety Disorder (GAD-7) scale, and questions about patients' self-perceived illness severity. Multivariate linear regression analysis was performed to explore factors that associated with mental symptoms, and a structural equation model (SEM) was used to assess the possible relationships between those factors and the patients' mental health. Results: Among the 85 participants, 45.9% had symptoms of depression (PHQ-9 >= 5), 38.8% had anxiety (GAD-7 >= 5), and 54.1% had insomnia (ISI >= 8). According to multivariate regression analysis, female sex, a higher level of interleukin (IL)-1 beta and greater self-perceived illness severity were all significantly associated with a higher PHQ-9 score, higher GAD-7 score and higher ISI score. In addition, the disease duration and the neutrophil to lymphocyte ratio (NLR) were positively related to patients' self-perceived illness severity. The results of the SEM analyses suggested that sex (beta = 0.313, P < 0.001), self-perceived illness severity (beta = 0.411, P < 0.001) and levels of inflammatory markers (beta = 0.358, P = 0.002) had direct effects on patients' mental health. The disease duration (beta = 0.163, P = 0.003) and levels of inflammatory markers (beta = 0.101, P = 0.016) also indirectly affected patients' mental health, with self-perceived illness severity acting as a mediator. Conclusion: A majority of COVID-19 infected inpatients reported experiencing mental health disturbances. Female sex, disease duration, levels of inflammatory markers and self-perceived illness severity are factors that could be used to predict the severity of patients' mental symptoms.