Background: Covid-19 disease has posed a serious challenge to countries' healthcare systems at the present outbreak. Meanwhile, the healthcare providers' mental health has been affected. This systematic review and meta-analysis aimed to investigate the pooled prevalence of depression, anxiety, and insomnia among healthcare workers in a short period during the COVID-19 pandemic. Materials and Methods: A systematic search was conducted through Web of Science, Scopus, Medline, and Embase databases, as well as preprint servers of medRxiv and SSRN, up to August 24, 2020. Results: This review comprised 69 articles with a total sample size of 108,931 individuals selected from medical staff. The pooled prevalence of anxiety, depression, and insomnia were 37% (95% CI: 31 to 43%), 34% (95% CI: 29 to 38%), and 39% (95% CI: 25 to 53%), respectively. A subgroup analysis showed that the prevalence of anxiety, depression, and insomnia was higher in females and nurses than in others. Conclusions: Findings indicated a high impact of the COVID-19 pandemic on the prevalence of anxiety, depression, and insomnia among medical professionals involved in the crisis with a variety of territories and occupations of both genders.