Abstract: Six non forage high fibrous tropical feeds were used to evaluate nutritive value using the in vitro gas production technique. The rumen mixed microbe inoculums were taken from fistulated Brahman-Thai native crossbred steers. The treatments were 1) palm meal (mech-extd), 2) palm meal (solv-extd), 3) leucaena meal (leaf and stem), 4) coconut meal (mech-extd), 5) mung bean meal and 6) dried brewer gain. The treatments were assigned to completely randomize design. The results indicate that soluble gas fraction (a; -7.91, -24.06, -2.11, -28.96, -10.31 and -4.35 mL, respectively), fermentation of insoluble fraction (b; 99.33, 124.06, 70.90, 128.96, 110.31 and 99.33 mL, respectively ), rate of gas production (c; 0.054, 0.071, 0.047, 0.122, 0.050 and 0.045 %/h, respectively) and potential of extent of gas production (a+b; 107.26, 148.13, 73.02, 157.93, 120.62 and 103.82 mL, respectively) were significantly different (P<0.01) among treatments. The cumulative gas volume at 24, 48 and 96 h after incubation were significantly different (P<0.01). These results suggest that coconut meal (mech-extd), palm meal (solv-extd), mung bean meal, palm meal (mech-extd) and dried brewer gain are exhibited high fermentability in the rumen.