The general aim is to identify the explanatory potential of alcohol use intentions in drinking behaviors in a sample of adolescents in Ecuador. The method consists of a descriptive, explanatory, and cross-sectional study using SEM techniques. The participants were 384 adolescents (57% male and 43% female), aged 14–18 years (M = 16.51; SD = 2.64), who are students attending between the 1st and 3rd year of high school in a public educational institution in Ambato, Ecuador. Like principal results, the presence of alcohol use intention is moderate; the practice of alcohol use is low and mostly does not represent a risk, although 3.9% of the participants could report significant problems with consumption. Intentionality and drinking covary positively with low and moderate intensity. Drinking Intentionality explained 15.3% of the variance of drinking. We conclude that the Alcohol Use Intentions are a predictor of adolescent drinking behaviors.