Thirteen individuals ranging in age from fifteen to forty years, who were known smokers of marijuana, all of whom died suddenly, were autopsied as coroner's cases. The pulmonary histopathologic changes revealed light to heavy infiltrations of pigmented monocytes within alveoli as well as varying degrees of monocytic and lymphocytic infiltration into the interstitium of the lungs. The intensity of the pulmonary infiltrate appears to be dose related. This report calls attention to the accelerated pathological changes in the lungs from marijuana smoking as compared to tobacco smoking leading to pulmonary scarring, emphysema, and eventual chronic obstructive pulmonary disease.