The 12-item Decentering Scale for Sport (DSS) is a sport-specific measure of decentering. Decentering refers to an individual’s ability to observe thoughts, feelings, and bodily sensations as transient mental events rather than truths or facts. A multistudy approach was adopted to develop the DSS. That is, five related studies were conducted to generate the pool of items, prove the content validity, confirm the dimensionality, and provide evidence on its factorial, convergent, concurrent, and discriminative validities. The unidimensional structure of the DSS was confirmed and repeatedly demonstrated. Overall, the DSS is a psychometrically sound measure of decentering in sports context, which can be used in future studies to examine the changing mechanisms of mindfulness on its adaptive and maladaptive outcomes.