The current study aimed to develop an adaptive behavior construct using National Longitudinal Transition Study-2 (NLTS2) data. The parent survey data gathered at Wave 1 was used to create an adaptive behavior construct. A bifactor model with three subdomains of conceptual, social, and practical skills with a total of 21 items was developed using confirmatory factor analysis (CFA) with acceptable fit indices (RMSEA = 0.049, CFI = 0.977, TLI = 0.971). The total score from the adaptive behavior construct was statistically significantly different across groups of youths with different levels of intellectual disability. The adaptive behavior construct created from the current study will allow for a series of research involving adaptive behavior variables within NLTS2 data.