This work is designed to study the possible causes of haematuria and haemoglobinuria and also the changes that may occur in blood and serum of 187 cattle and buffaloes in Assiut province. The recovered causes inducing such conditions are: hypophosphataemia, babesiosis, cystitis, and kidney affections. In hypophosphataemia, there was a decrease in haemoglobin concentration, total erythrocyte number, haematocrit value and the inorganic phosphorus while total leucocyte number and calcium remained normal. In babesiosis, the baemoglobin concentration total erythrocyte number, haematocrit value, calcium, inorganic phosphorus, Sodium were decreased while potassium level was increased. Chlorides and copper remained unchanged. In cystitis, the obvious changes were & sli ght increase in the total leucocyte count. The inorganic constituents of serum were not aff ected except a slight decrease in sodium and slight increase in potassium, In kidney affections; &-In acute nephritis. there was a slight increase in the total leu cocyte count and potassium while the level of copper was slightly reduced. In embolic nephritis, slight increase in the levels of chlorides and potassium, such increase was not significant.