The outbreak of the COVID-19 pandemic exerted significant mental burden on healthcare workers (HCWs) operating in the frontline of the COVID-19 care as they experienced high levels of stress and burnout. The aim of this scoping review was to identify prevalence and factors associated with burnout among HCWs during the first year of the COVID-19 pandemic. A literature search was performed in PubMed, Web of Science, and CINAHL. Studies were selected based on the following inclusion criteria: cross-sectional, longitudinal, case-control, or qualitative analyses, published in peer-reviewed journals, between January 1, 2020 and February 28, 2021. Studies carried out on other occupations than healthcare workers or related to other pandemics than COVID-19 were excluded. Following the abstract screen, from 141 original papers identified, 69 articles were eventually selected. A large variation in the reported burnout prevalence among HCWs (4.3–90.4%) was observed. The main factors associated with increase/ decrease of burnout included: demographic characteristics (age, gender, education level, financial situation, family status, occupation), psychological condition (psychiatric diseases, stress, anxiety, depression, coping style), social factors (stigmatisation, family life), work organization (workload, working conditions, availability of staff and materials, support at work), and factors related with COVID-19 (fear of COVID-19, traumatic events, contact with patients with COVID-19, having been infected with COVID-19, infection of a colleague or a relative with COVID-19, higher number of deaths observed by nurses during the COVID-19 pandemic). The findings should be useful for policy makers and healthcare managers in developing programs preventing burnout during the current and future pandemics. Int J Occup Med Environ Health. Int J Occup Med Environ Health. 2023;36(1):21–58