A total of 240 weaned pigs (Landrace ×Yorkshire × Duroc, 22±3 d of age, 5.16±0.90 kg initial body weight)were used to study the effect of feeding level of microbial fermented soya protein on their blood hematology,enzymes and immune cell populations. The microbial (Aspergillus oryzae + Bacillus subtilis) fermented soyaprotein (FSP) was used. Pigs were allotted to four dietary treatments, each comprising of 4 pens with 15 pigs.Basal diets consisted of 15% soya bean meal (Control diet); while for treatment diets SBM was replaced with3, 6 and 9% FSP. The experimental diets were fed from 0 to 14 day after weaning and then a commoncommercial diet was fed from 15 to 35 day. Blood was collected on 14 and 35 day of experiment and analyzedfor hematology, plasma aspartate transaminase (AST), plasma alanine transaminase (ALT) and immune cellpopulations. Increasing the level of FSP in the diet of pigs linearly decreased distribution of red blood cells(P<0.01), MPV (P<0.05), MO (P<0.05), EO (P<0.05) and BA (P<0.05) on d 14. Linear and quadratic decreasein the RBC (P<0.05), Hb (P<0.05), HCT (P<0.01), PLT (P<0.001) and EO (P<0.05) and linear increase in theMCHC (P<0.001), MPV (P<0.05), WBC (P<0.05) and NE (P<0.05) on d 35 was noted. Pigs fed with 6% FSPhad lower (P<0.05) levels of AST and ALT on d 14, while the levels of ALT and AST on d 35 did not differamong the dietary treatments. Thus the results suggest that microbial fermented soya protein affected thehematological indices, immune cell populations and plasma enzymes in weaned pigs.