This study intended to identify molecular characterization of Brassica through RAPD marker. The hereditary enhancement of Brassica cultivar is necessary for improved of yield and quality of various mustard varieties. Six Brassica cultivars have been used to assess inherent multiplicity and associations by PCR-based indiscriminate augmented Polymorphic DNA (RAPD) method. The available 6 varieties were BINAsarisha-4, BINAsarisha-5, Safal, Sampad, Rai-5, and Daulot. In this study, nine RAPD primers were used for assessment among them. 3 primers (OPA-02, OPB-01, and OPC-02) created 33 distinct polymorphic bands among 9. Different banding model generated by every primer with a standard of 11 score making bands. The primer OPA-02 formed an utmost quantity of the band (14) among 3 primers and the other 2 primers (OPB-01 and OPC-02) created 10 and 9 bands respectively. The cultivar Sampad (Brassica rapa L.) was very similar to Safal (Brassica campestris L.) with the lowest inherent space (0.0265). Sampad and Rai-5 (Brassica juncea, L.) showed the best hereditary remoteness (0.981). The findings will be helpful to take policy initiative for Brassica improvement program.