Cannabis sativa ssp. sativa is an annual plant that distributes in many provinces of North Vietnam, such as, Phu Tho, Thai Nguyen, Vinh Phuc and Bac Giang provinces. Up to now, there has been no research on Cannabis sativa ssp. sativa in Vietnam. The essential oil from leaves of the plant was obtained by steam distillation and yielded 0.1% by air-dried material. This essential oil was analysed by GC/MS and 30 constituents were identified. The major constituents found in the oil were: b-caryophyllene (22.49%), a-selinen (9.17%), β-selinen (8.37%) and humulene (6.01%).