Abstract The increase in feed costs has led feeder to replace protein source. Blood meal can be used in piglet diets instead of fish meal (FM). The objective of this study was to investigate the effect of fermented blood cells (FBCs) on the growth performance and intestinal health of weaned piglets. One hundred eighty 28‐day‐old piglets were assigned and were divided into 4 groups (9 L per groups and 5 pigs per litters) randomly. The piglets were fed one of four experimental diets, fish meal, blood cells (BCs), liquid‐state fermented blood cells (LFBCs) or solid‐state fermented blood cells (SFBCs) respectively. The dietary with LFBCs and SFBCs increased the average daily gain and feed intake (ADFI) and average daily gain (ADG) ( p < .05). In duodenum, LFBC group increased the villous height ( p < .05). The SFBC and LFBC group significantly increased the villous height ( p < .05) in the jejunum. Fermented blood cells exhibit a positive regulatory function on the intestinal tract and modulate intestinal microflora. Compared with the fish meal group, the CAT, GSH‐PX and SOD activity, and MDA level was no significant differences in jejunum and plasma of weaned piglets ( p > .05). LFBCs and SFBCs significantly increased the bifidobacteria and lactobacillus number in the caecum ( p < .05). Dietary LFBCs increased the expression of ZO‐1 mRNA in the jejunal of weaned piglets ( p < .05). In conclusion, dietary with fermented blood cells in weaned piglets had improved growth performance and intestinal health of weaned piglets.