Objective: to determine the relationship between family functionality and treatment adherence and compliance in patients with substance abuse disorder in “Instituto Nacional de Salud Mental Hideyo Noguchi – Honorio Delgado” in year 2021. Material and method: quantitative, observational, prospective, descriptive, and cross-sectional study. Our sample was of 153 patients, this was obtained by Epidat program, considering that 80% of patients improves their adherence to treatment with family support, with a precision of 5% and confidence level of 95 %. Three tests were used: APGAR familiar test to size family support, Test de Batalla to size knowledge and Test de Hermes to size treatment adherence. The information was analyzed in SPSS program version 21, using descriptive statistics and chi squared for the relationship of the desired variables. Results: 153 patients were interviewed, 6...