Background: During the COVID-19 pandemic, health workers’ workload is increasing, with the risk of burnout. Several instruments for assessing burnout have been developed since the concept was coined in the 1970s. It is important to map and describe the application of burnout instruments for health workers in the current COVID-19 pandemic situation. Aims: This article aimed to map and describe what instruments are used and variations of their application to research burnout in health workers during the COVID-19 pandemic. Methods: This scoping review searched articles systematically through 7 databases (PubMed, Clinical Key, Scopus, EBSCOhost, APA PsycINFO, Science Direct, and Wiley Online Library). Articles were screened and analyzed following the Arksey and O’Malley framework. Results: From 507 results, 31 peer-reviewed articles were selected. These studies involved 33,879 participants from various health professions. Generally, the research instrument is still dominated by Maslach Burnout Inventory. Applications of burnout measurements vary widely because there is no consensus on the concept of burnout assessment. Conclusion: Inconsistency in burnout-measuring tools can be seen as providing flexibility and alternatives, but at the same time, it is a gap that challenges researchers to develop more comprehensive instruments, especially for the burnout phenomenon in health workers during the COVID-19 pandemic.