Work-related burnout is common and has detrimental effects on employees in many industries. The current study aims to examine both environmental and personal factors that are associated with work-related burnout in a population of corporate employees who managed to retain their jobs amidst the global COVID-19 pandemic crisis. This cross-sectional survey served as the baseline data collection of a phase III wait-listed cluster randomised controlled trial (CRCT) of an intervention program on mental well-being at the workplace. Participants were recruited from six large-size corporations. Work-related burnout was assessed by the Maslach Burnout Inventory (MBI), and the Moos Work Environment Scale (WES) was used for evaluating the workers’ perspective on the workplace. Information was also collected on demographics and health behaviours. Burnout in this sample was prevalent with 60% of participants rated at a moderate to a high level on emotional exhaustion. Results from the multiple linear regression analyses suggested that different factors were related to different components of burnout. For example, age, work involvement, co-worker cohesion, and work pressure were associated with emotional exhaustion and depersonalisation while others were related to professional accomplishment. The overall results suggested that the work environment is of influential importance to the burnout of employees. However, although the study was conducted during the peak of the COVID-19 pandemic, the factors identified as relating to workplace burnout do not differ much from those identified in a crisis time. Implications of the results were discussed.