The effect of dietary Phosphorus (P) on nutrient and P digestibility in Thai-mdigenousxBrahman crossbred cattle was studied. The experimental design was a 4><4 Latin square design with 21 days period. Four male crossbred cattle of about 1.5±0.5 years-old and weighing 220±30 kg were randomly received 1 of 4 dietary treatments containing 1.9, 2.4, 3.1 and 4.2 g P kg^-1, respectively. The findings revealed that digestibilities of DM, OM, CP, NDF and ADF were not affected (p>0.05) by dietary P. However, P digestibility (818.71, 706.02, 625.25 and 537.90 g P kg^-1 diet) decreased (p<0.05), but plasma P (35.36, 40.66, 46.97 and 55.42 mgL^-1) increased (p<0.05) with increasing dietary P. The results indicated that dietary P affected (p<0.05) P digestibility and plasma P content in Thai-indigenousxBrahman crossbred cattle. The optimal dietary P for Thai-indigenousx Brahman crossbred cattle ranged from 1.7-3.1 g kg^-1 diet.