Objectives: To examine the validity and reliability of a modified Sedentary Behavior Strategy Self-Management Scale (SBSMS) in a sample of breast cancer survivors. Methods: A total of 291 African-American (AA) breast cancer survivors completed the SBSMS, which was subjected to tests of reliability, structural validity, and tests of measurement equivalence/invariance (ME/I). Results: A revised measurement model fit the data and demonstrated internal reliability and structural validity. Tests for ME/I revealed that the revised model had appropriate levels of invariance among weight status, educational, and years out from diagnosis groups, but not among age groups. Conclusion: The reliability and structural validity of the instrument was supported overall; however, revisions may be needed to support its validity in older AA breast cancer survivors.