Depression is a disorder that has been occurring with high frequency in the adolescent population, putting at risk the quality of life of those who suffer and their life. Behavioral Activation (AC) therapy has proven to be an effective treatment to combat it. It was proposed to implement The Brief Behavioral Activation Protocol for Depression (BATD-R) given its characteristics, which allow easy adherence to treatment. The objective was to estimate the effect of treatment on depressive symptomatology in six adolescents between 12 and 18 years of age diagnosed with this disorder that meet the established inclusion and exclusion criteria. The Brief Behavioral Activation Protocol for Depression (BATD-R) with a duration of one hour per week for ten weeks was applied to the participants. The main hypothesis was that the depressive behaviors of the consultants would decrease, and increase the healthy behaviors. The results showed that the application of the BATD-R in adolescents has a significant effect on the decrease of symptoms presented by an episode of depression or Major Depression Disorder, and also has an impact on healthy, depressive behaviors and reports of mood with statistically significant effect sizes for the three variables analyzed.