The purpose of the researchers in the study was to psychometrically evaluate Passion Scale scores (Vallerand et al., 2003) in exercise. Self-report data were collected from two samples of Greek exercise participants. Sample 1 (n = 217) provided data on the Passion Scale and the self-determination theory variables of perceived autonomy support by the exercise instructor, basic psychological needs, and exercise behavioral regulations. Sample 2 (n = 299) provided data on the Passion Scale and exercise enjoyment, inclusion of exercise into oneself, and frequency of mild, moderate, and strenuous exercise behavior. Confirmatory factor analysis supported the two-factor structure of Passion Scale scores. Evidence also emerged in favor of factor discriminant validity, internal consistency and convergent validity. In summary, the findings provided initial support in favor of the use of the Passion Scale in the exercise domain. (Contains 3 tables and 1 figure.)