Selecting of the adjuvant is one of the keys for the success of the vaccine application. Oil adjuvants, water-in-oil-in-water (W/O/W), have proved their efficacy in bovine vaccine as they induce rapid and long term immune response with various antigens. The present study was aimed towards improving and upgrading the locally prepared inactivated combined vaccine (Pneumo-4) containing Infectious Bovine Rhinotracheitis (IBR), Bovine Viral Diarrhoea (BVD), Parainfleunza type 3 (PI-3) and Bovine Respiratory syncytial (BRS) viruses using Montanide oil ISA206 as adjuvant and compare its efficacy with the commercial gel adjuvanted one. Both the commercial and prepared oil Pneumo-4 vaccines were administered twice to 6-9 months old seronegative calves through intramuscular (I/M) route with dose 5 ml, 21 days apart. Humoral immune response was followed up in the sera of vaccinated calves using serum neutralization test (SNT). The result revealed that both adjuvanted vaccines gave a significant effect on all vaccinated animals but the oil adjuvanted vaccine was particularly better and effective than gel adjuvanted where oil adjuvanted vaccine induced early intense immune response and showed prolongation of antibody secretion in comparison to the Aluminium Hydroxide gel