Abstract The existing literature largely focuses on health risks and other pharmacodynamics of using cannabis, with fewer investigations of other normative psychological effects from consumption among otherwise healthy people. We measured several basic constructs of social psychology corresponding to the concept of prosociality among 146 healthy young adults between 18 and 25 years (M = 18.9, SD = 1.4) with varying detectable levels of tetrahydrocannabinol (THC) in their urine, controlling for participant’s sex, age, ethnicity, and childhood socio-economic status. Compared to THC-free individuals, cannabis users scored higher than non-users on validated measures of Prosocial Behaviors (d = .34, p = .04), the Empathy Quotient (d = .36, p < .01), Moral Harmlessness (d = .76, p < .01) and Moral Fairness (d = .49, p < .01), but exhibited a...