BACKGROUND During a pandemic, healthcare workers (HCWs) are exposed to many stresses that predispose them to psychological disorders. This study aimed to evaluate the impact of the coronavirus disease 2019 (COVID-19) pandemic on the anxiety and depression level of HCWs and determine the relationship between them in terms of their demographic characteristics. METHODS This study used a cross-sectional design. The participants consisted of clinical, administrative, and cleaning staff who were working in a referral COVID-19 hospital in an urban area of Iran. The census sampling method was used for recruiting the participants from May to August 2020. The Generalized Anxiety Disorder-7 (GAD-7) questionnaire and the Center for Epidemiologic Studies Depression (CES-D) Scale were employed to collect data. Then, data were analyzed using multivariable linear regression analysis. RESULTS One hundred forty HCWs participated in this study. The mean scores of anxiety and depression were 6.64 (4.86) and 18.21 (10.59), respectively. There was a significant direct association between anxiety and depression (P < 0.001). In addition, female gender (P = 0.01) and having a history of infection with COVID-19 (P = 0.001) were associated with a higher level of anxiety. Moreover, having a history of being quarantined due to COVID-19 was associated with a higher level of depression (P = 0.03). CONCLUSIONS According to the findings of the present study, considering the mental health of HCWs during the generalized anxiety outbreak of COVID-19 should be a priority, and appropriate interventions should be planned to improve their psychological condition.