The aim of this study was to examine the effects of replacing soybean meal (SBM) with increasing levels (0%, 33%, 67%, and 100%) of sugarcane yeast and urea on the intake, performance, and feeding behaviour of buffalo heifers. Twenty Murrah female buffalos with an initial average weight of 157 ± 1.9 kg at 7 months old were distributed in a completely randomized design. The experimental period was 84 days, and was preceded with 30 days of adaptation. Data were subjected to analysis of variance and regression, using the GLM and REG procedures of SAS software at 5% probability level. The replacement of SBM with sugarcane yeast did not have a significant effect on the intake of dry matter (DM), organic matter and crude protein (CP). Non-fibrous carbohydrate intake increased linearly, whereas the intake of neutral detergent fibre (NDF), and ether extract (EE) decreased linearly. There was no treatment effect on average daily gain or feed conversion (FCR). Rumination efficiency on nondetergent fibre (NDF) decreased linearly. The times spent ruminating, remaining idle, and feeding were not influenced by the treatments, and neither were the parameters of feeding efficiency as a function of DM and NDF intakes and rumination efficiency as a function of DM intake. Dry sugarcane yeast and urea could replace SBM fully in the diet of buffalo heifers with a roughage to concentrate ratio of 50 : 50, because animal performance would not be affected.