Three proteins were isolated from plant parts of Trichosanthes cucumerina L. var anguina (L.) Haines, they were TF2 from fruit, TS3 from seed and TR3 from root with molecular masses (Mr) approximately 16 - 64 kDa on SDS-PAGE characterization. The proteins were extracted with Phosphate Buffer Saline (PBS), then they were precipitated using 80% saturated ammonium sulphate continued with the dialysis using cellophane. The dialysate was fractionated through gel filtration chromatography. The highest yield of protein was 1.109% from the seed (TS3), then 0.356% from the root (TR3), while the lowest was 0.014% from the fruit (TF2). The Lethal Concentration 50 (LC ) of proteins on brine shrimp lethality test was 50within range of 19 μg/ml - 25 μg/ml. The cytotoxicity test of the TR3 and TS3 proteins on cancer cell lines indicated that both of the proteins could inhibit proliferation of HeLa and K-562 cells with IC up to 45 μg/ml. It is recommended to conduct further researches on 50Trichosanthes plant as a herbal medicine to treat cancer.