COVID-19, being the most terrible occurrence of the 21st century, has profoundly affected the physical and mental well-being of healthcare workers (HCWs). Throughout this pandemic, HCWs have been at the forefront, confronting numerous physical and mental health problems. Our study aimed to identify the major mental health issues experienced by HCWs in Dhaka City, Bangladesh. Additionally, we aimed to uncover the contributing factors that led to their heightened stress. According to this purpose, this cross-sectional study was conducted from June 2021 to February 2022 with different categories of HCWs selected from twelve hospitals exclusively designated for COVID-19 patients. Data were collected through face-to-face interviews using semi-structured questionnaires. A 10-item Perceived Stress Scale (PSS) was used to assess the stress levels experienced by the respondents. Among the total of 483 HCWs, 76.6% were nurses, 19.9% were doctors, and 3.5% were medical technologists. Our study found that the prevalence of COVID-19 positive cases among HCWs (nurses, doctors, and medical technologists) was 28.6%. Based on the PSS, 93.2% experienced low to moderate levels of stress, and 6.8% reported high levels of stress. A number of sociodemographic, habitual, organizational, and family factors of the respondents were significant, with the PSS at a 5% level of significance and a p-value less than 0.05. However, the variable ‘experience of any negligence, torture, blaming/bullying/threat from society’ was insignificant to the stress experienced by the HCWs. In brief, the study highlights the mental health issues faced by HCWs amid the pandemic, emphasizing significant associated factors. Organizational support and the role of the HCWs' families are crucial in reducing their stress levels.