A highly potent pneumo-4 vaccine of combined inactivated Bovine Viral Diarrhea Virus, Infectious Bovine Rhinotracitis Virus, Parainfluenza-3 Virus and Bovine Respiratory Syncytial Virus could play a valuable role in respiratory disease control program in calves. In this study we determined the influence of virus concentration by polyethylene glycol (PEG) precipitation, and the use of montanide oil & gel as adjuvants on the immune response of calves to the inactivated Pneumo-4 vaccine. Two batches of concentrated viruses' vaccine were prepared, one adjuvanted with aluminum hydroxide gel and the other adjuvanted with oil. Both batches administered twice to six-month-old seronegative calves through intramuscular (IM) route. Different doses, 2ml, 2.5ml, and 3ml of the concentrated gel adjuvanted & 2.5ml,3ml and 3.5ml of concentrated oil vaccine were tested compared with 5ml for the commercial un-concentrated Pneumo-4 vaccine. The induced BVDV, IBRV, PI-3V and BRSV antibodies were followed up in the sera of vaccinated calves up to12M post vaccination (M.P.V.) using Serum Neutralization Test (SNT). The result revealed that concentration of viruses by PEG improve the quality of antigen used in the vaccine formulation to produce a good quality combined inactivated vaccine. Also, both concentrated 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 protective immune response and showed prolongation of antibody secretion in comparison to the Aluminum Hydroxide gel.