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Genetic diversity of Ralstonia solanacearum, causal agent of bacterial wilt of tomato was assessed by using three different molecular methods such as random amplified polymorphism DNA (RAPD), BOX-PCR and hrp (hypersensitive response and pathogenicity) gene sequence analysis technique. Twelve isolates of Ralstonia solanacearum belonging to biovar 3 (9 isolates) and 4 (3 isolates) were collected from Northern parts of India including Himachal Pradesh and Uttarakhand states from infected tomato plants. Out of 16 primers used in RAPD fingerprinting, four primers (OPA-2, OPA-11, OPC-5, OPE-7) showed monomorphic bands and remaining 12 primers exhibited polymorphic amplified products of both the biovars of R. solanacearum. The primer OPE-10 showed the highest level of genetic diversity among the isolates. Ten isolates of R. solanacearum were classified into two clusters at 20 per cent similarity coefficient and cluster 1 represented all isolates of biovar 3 (UTT-23, UTT-10, UTT-26, HPT11, UTT-9, UTT-32, HPC-3) and cluster 2 comprised the biovar 4 (UTT-22, HPT-3, UTT-24). BOX-PCR fingerprint of R. solanacearum clearly distinguished biovar 3 and 4 grouped into two distinct clusters at 40% similarity coefficient. Cluster 1 represented all isolates of R. solanacearum biovar 3 and cluster 2 comprised the biovar 4 isolates. The isolates of R. solanacearum have genetic diversity in hrpB gene, but it could not differentiate the isolates of biovar 3 and 4. However, the biovars 3 and 4 of R. solanacearum can be genetically distinguished by using BOX- PCR and specific primer of RAPD.