A total of 96 pigs (Duroc×Landrace×Yorkshire) weaned at day 21 with an average initial body weight of 6.68 kg were used to investigate the effects of sodium butyrate on the growth performance, intestinal microflora and morphology of weanling pigs. The pigs were allocated to three dietary treatments in a randomized complete block design, each treatment was replicated four times with eight pigs per replicate and the trial lasted for 30 days. The dietary treatments were: 1. basal diet, 2. basal diet + 500 mg/kg sodium butyrate, 3. basal diet + 1000 mg/kg sodium butyrate. Diets were formulated according to requirements of NRC (1998) for 10-20 kg pigs. All diets were fed as mash, and no antibiotics was included. The results showed that supplementation with 1000 mg/kg sodium butyrate improved (P<0.05) growth performance, reduced (P<0.05) the total viable counts of intestinal Clostridium and Escherichia coli, decreased (P<0.05) tumor necrosis factor-α (TNF-α) and interleukin- 6 (IL-6) levels in the serum, and increased (P<0.05) villus height and the villus height to crypt depth ratio at the small intestinal mucosa as compared with control. The results indicated that sodium butyrate is effective in enhancing the growth and intestinal morphology of weanling pigs.