To investigate mental health symptoms (anxiety, depression, and sleep status) and their associated factors among people infected with the SARS-CoV-2 omicron variant during the quarantine period in Shanghai. To investigate the mental health symptoms among participants with SARS-CoV-2 omicron infection, an anonymous online survey questionnaire was used. The survey panel included the 9-item Patient Health Questionnaire-9 (PHQ-9), 7-item Generalized Anxiety Disorder Scale (GAD-7), Pittsburgh Sleep Quality Index (PSQI), and 22-item Ruminative Responses Scale (RRS). Group comparisons and correlation analyses were employed to explore the epidemiological characteristics of patients and factors related to depression and anxiety symptoms. A total of 960 participants completed the survey. Of the total respondents, 583 participants (60.7%) were male, and the mean (SD) age was 34.33 (9.21) years (95% CI: 33.74-34.91). The prevalence of depressive and anxiety symptoms among the participants was 13.7% (n=151, 95% CI: 11.6%-15.7%) and 8.6% (n=90, 95% CI: 6.9%-10.3%), respectively. Age-stratified analysis showed that the prevalence of anxiety among the 36- to 45-year-old group (12.9%; n=35, 8.9%-16.9%) was significantly higher than that of the 18- to 15-year-old group (7.4%; n=42, 5.3%-9.6%, p=.011). Spearman's correlation analyses showed that rumination (assessed by the RRS) was significantly and positively correlated with depression (rho=.706, p<.001) and anxiety symptoms (rho=.758, p<.001). The results suggest that female and middle-aged populations manifest higher susceptibility to mental health distress during the current Omicron wave of the COVID-19 pandemic. Population-specific psychological crisis intervention is warranted to improve the quality of epidemic prevention methods and to promote the mental well-being of the public.