Background Adaptive behaviour is an important characteristic of people with intellectual disabilities, and it has been associated with the individual’s requirements to performance adequately in the social context. Indeed, measuring adaptive behaviour indicates what an individual does independently, without help, support, reminders, or prompts. Peru has a particular society and there is not an accessible scale to evaluate the adaptive behaviour in people with intellectual disabilities. We proposed to create and obtain evidence of validity and reliability of a new Adaptive Behaviour Test for people over 15 years old with intellectual disabilities with interest in being part of the economically active population.Methods We used a qualitative approach to construct the test, the Aiken V coefficient to assess content validity, and Krippendorff's alpha for inter-observer reliability. We performed an exploratory and confirmatory factor analysis to assess the internal structure and consistency to check the homogeneity between the proposed items. We performed convergent validity to analyze the relationship of the test with other variables.Results We obtained a 25-item test with three dimensions: a) activities of daily living; b) instrumental skills and c) communication. Aiken's V coefficient, Krippendorff's alpha, factor analysis and internal consistency allowed us to identify the most important items and confirm the factors. convergent validity with quality of life was demonstrated.Conclusion The developed scale is a useful screening test for the measurement of adaptive behavior and the monitoring of social and labor inclusion programs, the results show that the items and factors contribute to the measurement of the construct.