The study was conducted to evaluate the effects of microencapsulated probiotics and prebiotics in broilers. A total of 108 one-day-old male Arbor Acres broilers were randomly divided into 3 groups (CON: basal diet; MEP: basal diet + compound microecologic products; ANT: basal diet + antibiotics), and there were 6 replicates per group and 6 birds per replicate. Compared with CON, diets supplemented with MEP or ANT significantly increased average daily gain and serum immunoglobulin M level at day 21, and serum total antioxidant capacity (T-AOC) level at day 42. Compared with CON and ANT groups, birds in MEP group had greater serum T-AOC, immunoglobulin A, interleukin-2 (IL-2) levels, and caecal Lactobacilli counts at day 21, and had greater serum IL-2, interleukin-6 levels, and caecal Lactobacilli counts at day 42. In conclusion, compound microecologic products had beneficial effects on body weight gain, serum immune function, and caecal Lactobacillus counts in broilers, which can be recommended as alternative to antibiotics.