This study aimed to evaluate the clinical diagnostic value of some acute phase proteins (Haptoglobin, C- reactive proteins, fibrinogen) as a markers of infection and inflammation in buffaloes affected with mastitis and with pneumonia. twenty buffaloes (4-6 years) suffering from acute mastitis and 20 buffalo-calves (3 – 6 months) suffered from pneumonia were used in this study. The apparently healthy groups included 10 buffaloes and 10 buffalo-calves, served as control. The animals belonged to some private farms in Sharkia Governorate. Milk samples were collected from mastitic buffaloes, and nasopharyngeal swabs were collected from pneumonic buffalo-calves for bacteriological examination. Blood samples were collected also for determination of serum total proteins, albumin, CRP, Hp and plasma Fb. The obtained results revealed a significant increase in Hp, CRP, and Fb levels in diseased animals than healthy ones. Also, an increase in serum total proteins accompanied with a decrease of serum albumin in diseased animals was observed. From this study, it can be concluded that, the inflammatory markers (Hp, CRP, Fb) may act as an early indicators of infection and inflammation in some diseases in buffaloes.