According to The World Health Organization (WHO), there are approximate 80 percent of population relied on traditional medicines, especially the medicinal plants in initial health care. In the research and development process of drugs, experience of using traditional medicines is one of the most important factors that create the increasing in the success rate of searching for leading compounds through reducing time consuming, saving costs and being less harmful to living bodies. Therefore, medicinal plants are always considered as an attractive subject that significantly stimulates the attention of scientists worldwide. According to the Dictionary of Vietnamese medicinal plants, Glochidion in Vietnam has many species used as drugs and medicine for treatment of diseases such as: Glochidion daltonii cures bacillary dysentery; Glochidion eriocarpum Champ cures inflammatory bowel and dysentery, allergic contact dermatitis, itching, psoriasis, urticarial (hives), and eczema; At the Institute of Medicinal Materials, Leaves of Glochidion hypoleucum are used to strengthen tendons and bones and recover wound; Glochidion hirsutum is often used to cure diarrhea, indigestion, abdominal bloating, and its leaves are used for snake bites, etc. Researches on chemical compositions show that Glochidion contains many layers of interested substances such as terpenoids, steroids, megastigmane, flavonoid, lignanoid and some other phenolic forms. Biological evaluation studies show that the extracts and compounds isolated from these species have interested activities such as cancer cytotoxic, antifungal, antimicrobial, antioxidant, Therefore, the thesis title was chosen to be “Study on chemical constituents and cytotoxic activities of Glochidion glomerulatum and Glochidion hirsutum growing in Vietnam”.