Abstract: Abstract: 80 ten-day-old chickens being healthy and having even weight were randomly divided into 4 groups,20 for each group. The first group was control group injected physiological brine. Chickens from the second to fourth groups were respectively injected 1000 units,10000units and 100000 units α-interferon. Immune organ index number, lymphocyte conversion ratio, interleukin-2 content, Serum complement activity were determined. The results showed that Immune organ index number, lymphocyte conversion ratio, interleukin-2 content, Serum complement activity of the third group were higher than the others.