The current coronavirus disease-2019 (COVID-19) pandemic constitutes a significant public health problem worldwide, as well as mental health problems. This study aimed to evaluate the mental health of COVID-19 survivors, considering their sociodemographic, clinical, and immune variables. A cross-sectional and correlational study was conducted on 318 COVID-19 survivors from one hospital in Peru. Through telephone interviews, evaluation of the presence of depressive symptoms using the Patient Health Questionnaire-9, anxiety symptoms through the Generalized Anxiety Disorder-7, somatic symptoms through Patient Health Questionnaire-15, and posttraumatic stress disorder (PTSD) symptoms through Impact of Event Scale-Revised was carried out. Poisson regression analyses were performed with their adjusted variances to calculate the prevalence ratio (PR) with their 95% confidence interval. All regression models were adjusted (PRa) for follow-up time. A significant proportion of patients have depressive (30.9%), anxious (31.1%), somatic (35.2%), and PTSD (29.5%) symptoms. The variables associated with a higher frequency of clinically relevant mental symptoms were female sex, self-perception of greater COVID-19 severity, presence of persistent COVID-19 symptoms, loss of a family member due to COVID-19, and prior psychiatric diagnosis or treatment. In addition, the neutrophil-to-lymphocyte ratio was significantly higher in patients with clinically relevant symptoms of depression. COVID-19 survivors showed a high prevalence of negative mental symptoms. Our findings help to identify patients who are vulnerable and require psychiatric care.