In recent years, integration between National Federations (NFs) and National Disability Sport Organizations has been progressing steadily among the Paralympic superpowers. However, the NFs in Japan have not made substantial progress with integration and inclusion for disability sports, and have fallen behind other nations. Most studies of integration and inclusion covering sports organizations have focused on the current situation, and no research based on an academic framework has been conducted (e.g., Nogawa et al., 2012; Nogawa et al., 2013; Sasaki et al., 2011; Tanaka, 2014). The present study focused on: (I) measurement of integration and inclusion of NFs in Japan using the OCIIS (Fay, 1999) and (II) validation of OCIIS adaptability. First, we established hypotheses for the OCIIS comprising 6 stages and classified 54 NFs that had joined the Japan Olympic Committee based on integration and inclusion level. Second, we extracted 9 NFs for each stage classified on the basis of the first study and interviewed key informants. This revealed that the integration and inclusion level of the NFs in Japan could be classified into 5 stages. Twenty-five NFs were at stage 1 (no awareness of disability sport), 5 NFs were at stage 2 (conducting activities for awareness of disability sport), 10 NFs were at stage 3 (existence of corresponding National Disability Sport Organizations in the NFs / electing a board member or a councilor of the NFs from the National Disability Sport Organizations / hosting or co-hosting national-level disability sport competitions), 12 NFs were at stage 4 (establishing a disability sport or Paralympic committee) and 2 NFs were at stage 5 (joining the Japan Paralympic Committee).