Objective·To explore the clinical characteristics and therapy of cannabis abuse among adolescents and college students. Methods·Clinical data of two college students with cannabis abuse were reported and medical treatment of cannabis abuse was summarized. Results·Cannabis abuse can result in severe psychiatric symptoms, including hallucination and delusion. Some patients may have emotional problem. Antipsychotic treatment can effectively alleviate symptoms. Conclusion·Cannabis abuse is harmful to young people. Relevant institutions should pay attention to cannabis abuse and implement related measures to prevent cannabis abuse among adolescents and college students.