Ninety-six young pigs were used to investigate the effect of dietary supplementation with medium-chain triacylglycerols (MCT) on growth performance and intestinal microbial counts. The pigs were divided into four treatments, with four replicates per treatment. Six pigs were assigned per replicate and were fed diets supplemented with 1. 6.0% soyabean oil (SO), 2. 4.8% SO + 1.2% MCT, 3. 3.0% SO + 3.0% MCT, or 4. 1.2% SO + 4.8% MCT for 28 days. The results showed that dietary supplementation with 4.8% MCT improved the gain-to-feed ratio of the pigs (P < 0.05). Dietary supplementation with 3.0% MCT decreased the lactic acid bacteria (L) counts in the stomach and caecum, while supplementation with 4.8% MCT decreased the L counts in the stomach and the small intestine (P < 0.05). Dietary supplementation with MCT increased the L-to-coliforms (C) ratio in the colon and rectum (P < 0.01) and decreased L+C in the stomach (P < 0.05). In conclusion, dietary supplementation with 4.8% MCT may change the intestinal microbiota and improve the feed utilization efficiency of young pigs.