Thirty five cyclic buffalo cows (20 in the cold season and 15 in the hot season) 3-9 years in age and 1-7 in parity were used in this study. Oestrous behaviour was monitored 24 hrs per day, using a closed TV circuit and night illumination, beside direct visual observations. Teaser bull was absent in the first half and present with buffalo cows in the second half of each season. Blood samples were withdrawn from each animal twice a week, for plasma progesterone determination by radioimmunoassay in order to detect false oestrus, ovulation and quiet ovulation. The most frequent sign of oestrous behaviour was restlessness (87.90%), followed by walking along side the wall (81.45%) and bellowing (78.23%). The least frequent sign was vulvar swelling (6.29%), followed by boating and vaginal mucus discharge (17.74% for each). Signs of the mutual behaviour with male recorded frequency higher than those of self oestrous behaviour and ranged from 83.94 to 87.27%.                 About half the number of oestrus signs commenced and terminated within 6-14 hrs. A moderate intensity of oestrus (exhibiting 7-14 signs) represented 67.83% of total oestrus cases, while strong or weak oestrus represented only 15-17% of total oestrus cases. Incidence of oestrous behaviour increased in the cold season during day and day / night period, while that in the hot season increased during night and night / day period, indicating that season may modify diurnal variation of the oestrous behaviour in buffaloes. Percentages of quiet ovulation and false oestrus were 1.25 and 14.13 in the cold season versus 3.70 and 10.34 in the hot season, respectively. Mean length of oestrus period was 11.18 hrs, while the estrous cycle length was 24.32 days, and both traits were not significantly influenced by season.