Pasteurellosis is one of the important economic diseases in ruminants, especially in cows and buffaloes. It is caused by Pasteurella multocida and occasionally by Mannheimia haemolytica. The aim of this study was to isolate Pasteurella multocida from lungs with probable mentioned bacterial agents in cows and buffaloes in Urmia's slaughter house. 240 lung samples over a period of 12 months were cultured. The results have revealed 6 (2.5 %) Pasteurella multocida results suggest that the animal, its breed, sex, age and season can be effective in the occurrence of these positive cases. The positive samples were all from male beef cattle of hybrid breeds (4 samples) in winter and Holstein breeds (2 samples) in spring.