Stigma among healthcare workers during the coronavirus disease 2019 (COVID-19) pandemic is an issue that requires immediate attention, as it may otherwise lead to the collapse of healthcare systems. In this study, we developed the COVID-19-related stigma scale for healthcare workers (CSS-HCWs) and assessed its reliability and validity. Data were collected online from 500 participants, including physicians and nurses involved in COVID-19 care. The first item of the draft scale was developed based on a literature review and qualitative study. The draft scale consisted of 24 items, which were rated on a six-point Likert scale. Descriptive statistics were calculated and the data distribution was analyzed. To assess the scale’s validity and reliability, structural validity was evaluated through an exploratory factor analysis. Criterion-related validity was examined through a correlation analysis using the E16-COVID19-S, a COVID-19 scale developed for physicians in Egypt. Reliability was evaluated by examining the scale’s stability and internal consistency. The findings revealed that the stigma scale was a valid and reliable instrument. The final scale consisted of 18 items across three domains: personal stigma, concerns of disclosure and others, and family stigma. In conclusion, the scale is a valid and reliable instrument that can measure COVID-19-related stigma among healthcare workers.