PURPOSE: The study aims to conduct the Turkish validity and reliability study of the Mishel uncertainty in illness scale-community form. DESIGN AND METHODS: This is a study with a methodological design. It was carried out in a family health center in a province in the Black Sea Region between May and October 2019. The sample of the study consisted of 479 individuals with chronic diseases. The data were analyzed with exploratory and confirmatory factor analysis. FINDINGS: The Cronbach's alpha was found to be 0.79. The fit indices of the 20-item scale with three-factor structure are at an acceptable level (root mean square error of approximation: 0.056; comparative fit index: 0.926; incremental fix index: 0.927; goodness of fit index: 0.918; Tucker-Lewis index: 0.915; adjusted goodness of fit index: 0.896; χ /SD: 2.481, p < 0.001). PRACTICE IMPLICATIONS: The level of uncertainty revealed by the scale gives information about the chronic disease management of individuals.