To estimate the immune response against Pasteurella multocida B:2 in cattle and buffalo, different serological assays have been used as agglutination and indirect haemagglutination assay (IHA), but none is highly sensitive. Enzyme Linked Immunosorbent Assay (ELISA) has been effectively used to determine the immune status in vaccinated cattle and buffalo. It was developed by using purified recombinant outer membrane H protein (rOmpH) as coating antigen of P. multocida B: 2. The optimum condition for this assay was 1/800 coated rOmpH antigen (1.22 ug/mL), 1/400 dilution of primary sera and 1/5000 dilution of the conjugate. The cut-off value was calculated as 0.101. The sensitivity and specificity of developed ELISA was 92 and 86% respectively. Positive and negative predictive value was 87.42 and 91.6% respectively. This finding suggests that an in-house indirect ELISA is highly sensitive than IHA and can be used to monitor the bovine antibodies against hemorrhagic septicemia in Pakistan.