To systematically review the evidence evaluating validity or reliability of self-reported and device-based instruments to measure PA in individuals who use a wheelchair and making recommendations for the selection of PA outcomes tools .Pubmed, Embase, and CINAHL were systematically searched.Studies reporting measurement properties of instruments to assess PA in individuals who use a wheelchair.The COSMIN checklist was used to assess the methodological quality of the included studies and the measurement properties of instruments assessing PA were examined.The search yielded 5341 records, 61 were considered relevant, 21 articles were included. A best evidence synthesis was performed on nine studies including four self-reported instruments and thirteen studies including eight device-based instruments. One study evaluated both self-reported and device-based instruments. The overall methodological quality of all studies ranged from poor to excellent. Variable levels of evidence were found for both the validity and reliability for self-reported instruments and for criterion validity for device-based instruments.The PASIPD and PARA-SCI seems the most promising self-reported instruments for measuring the intensity of PA. Device-based instruments that can be used for measuring both the intensity and type of PA are the GENEactive, Actigraph GT3X+, Actiheart or the PAMS, showing moderate evidence for a positive rating of criterion validity. For measuring the type of PA the PAMS and VitaMove are suitable, showing both good evidence for a positive rating of criterion validity.