The aims of the present research were to study the effectiveness of fermented buffalo milk (dadih) to control cancer diseases by mice. The research was initiated by preparing dadih fermented with Lactococcus lactis mutant (Dadih SML). The dadih SML product was firstly tested for their toxic potent by using shrimp juvenile (prawn larva of Arthemia Leach Salina) according to method of Brine Shrimp to define the activity of anticarcinogenic potent of dadih. Dadih SML assesses LC50 of 357.7252 g/ml. It means that dadih SML could pursue cancer. Dadih SML was then tested to 18 female mice (Mus musculus) which have been treated with carcinogenic compound of benzoepiren. Dadih SML was offered to mice in three doses: 70 mg/20 BB g, 126 mg/20 BB g and 210 mg/20 BB g. As positive control was used nisin in two doses: 14.4 mg/20 BB g and 4.2 mg/20 BB g and negative control was distilled water by 0.4 ml/20 BB g. The animals were induced for 10 days by benzoepiren 0.3 mg/20 BB g, and followed for 15 days by tested compound. The results showed that dadih SML with doses of 210 mg/20 BB g could effectively encounter cancer bump volume 72,513 % where heavy change of body and also result of autopsy show normally.