Abstract: The objective of this study was to determine protein requirement of Thai native cattle compared with the meta-analysis of Bos indicus. The 24 Thai native cattle with body weight of 134 + 11.2 kg were arranged in a randomized block design with 8 replications and 3 treatments. Cattle were fed with total mixed ratio consisted 3 levels of protein (6.0, 9.0 and 12.0%). The meta-analysis of protein requirement for maintenance and for growth of Thai native and Brahman cattle were used to compare with the experiment. A database from 48 observations of trials conducted under diverse feeding condition in Thailand was subjected to regression analysis using a linear model. Dry matter, organic mater, crude protein and Neutral Detergent Fiber (NDF) digestibility, N absorption and N retention increased (p<0.05) with increasing levels of CP. Prediction equation CP intake (CPI, gCP kg‾¹ BW^0.75) with relation to Average Daily Gain (ADG, g kg‾¹ BW^0.75) was CPI = 0.413+4.28 (R² = 0.896, SE = 0.774, p<0.05, n = 24). It can be explained that the CP for maintenance of Thai native cattle is 4.28 gCP kg‾¹ BW^0.75. Results from the meta-analysis, the relation between Nitrogen Intake (NI, g kg‾¹ BW^0.75) and Nitrogen Retention (NR, g kg‾¹ BW^0.75) of Thai native were NR = -0.41 (SE = 0.16)+0.58 (SE = 0.10) NI (n = 26, R² = 0.57, RSD = 0.27, p<0.05) and Brahman were NR = -0.34 (SE = 0.1)+ 0.70 (SE = 0.04) NI (n = 14, R² = 0.96, RSD = 0.20, p<0.05). The relation between NI and Dry Matte Digestibility (DMD, %) for Thai native were DMD = 48.90 (SE = 4.92)+11.10 (SE = 3.02) NI (n = 12, R² = 0.57, RSD = 4.90, p<0.05) and Brahman were DMD = 48.55 (SE = 6.44)+7.16 (SE = 1.94) NI (n = 11, R² = 0.60, RSD = 7.47, p<0.05). The relation between NI and Organic Matter Digestibility (OMD, %) for Thai native were OMD = 56.68 (SE = 2.75) + 5.27 (SE = 1.72) NI (n = 12, R² = 0.48, RSD = 2.78, p<0.05), Brahman were OMD = 5 0.79 (SE = 3.75)+6.18 (SE = 1.13 ) NI (n = 11, R² = 0.77, RSD = 4.35, p<0.05). The relation between NI and NDF Digestibility (NDFD,%) for Thai native were NDFD = 50.94 (SE = 1.16) + 4.26 (SE = 0.70) NI (n = 8, R² = 0.86, RSD = 1.01, p<0.05), Brahman were NDFD = 51.52 (SE = 2.80) + 5.60 (SE = 0.79) NI (n = 9, R² = 0.88, RSD = 2.80, p<0.05). The relationship between NI and CP digestibility (CPD, %) for Thai native were CPD = 47.86 (SE = 4.50)+13.09 (SE = 2.76) NI (n = 11, R² = 0.71, RSD = 4.29, p<0.05). The relationship between NI and Blood Urea Nitrogen (BUN, mg %) for Thai native were BUN = 7.56 (SE = 1.36) + 0.09 (SE = 0.11)NI (n = 9, R² = 0.08, RSD = 2.86, p<0.05), Brahman were BUN = 14.17 (SE = 3.04)-1.21 (SE = 0.95) NI (n = 4, R² = 0.45, RSD = 2.75, p<0.05). The relationship between NI and ruminal Ammonia Nitrogen (NH₃N, mg%) for Thai native were NH₃N = -7.99 (SE = 3.07) + 12.14 (SE = 1.84) NI (n = 7, R² = 0.90, RSD = 1.56, p<0.05. The results indicated that protein requirement by nitrogen intake of Thai native and Brahman have relation to nitrogen retention, DMD, OMD, NDFD, ADFD, CPD, BUN and NH₃N but the potential of prediction were indicated to R² value.