Enjoyment is often cited as an important correlate of physical activity behavior and is included in many health promotion models and theories of behavior motivation. A number of measures (scales) have been developed and used to quantify enjoyment of physical activity but most lack sufficient validity evidence. In addition, little is known about how the various measures interrelate. Therefore, the purpose of this research study was to compare and extend the construct validity evidence for several measures of physical activity enjoyment. Five enjoyment scales were chosen for comparison. Confirmatory factor analysis was used to examine the factor validity, invariance, and convergence of the enjoyment scales. If the hypothesized factor structure failed to fit the data, exploratory analyses were used to determine a better fitting model. In addition, each measure of enjoyment was correlated with several estimates of physical activity, perceived competence and extrinsic motives for physical activity. Participants (N = 1023; mean age 19.60 1.55 years) were recruited from basic physical education classes and the psychology research pool at two universities. A simple single factor model did not adequately account for the covariance among the items on four of the five scales. Correlated uniquenesses were added to the models for the PACES-M, GEQ, and IMI-joy to improve model fit. Based on exploratory analyses, a two factor model was found to represent the data from the PACES. The factorial invariance between black and white and between male and female participants was supported for all scales. The results support the similarity of enjoyment scale scores, but suggest that measuring enjoyment and perceived competence with the same instrument (i.e IMI and MPAMR) inflates their relationship. Each measure of enjoyment was modestly correlated with total and vigorous physical activity (0.22 0.34), but only slightly related to work and moderate activity (0.047 0.12). As expected, the correlations of enjoyment with perceived competence were larger than with the extrinsic motives. The magnitude of these relationships was very similar across the five measures of enjoyment. Overall, this research provides support for the construct validity of scores from several measures of physical activity enjoyment, supporting similarity of measurement but not complete convergence. Key Words: Confirmatory factor analysis; Enjoyment; Physical Activity; Validity