The effects of methionine (Met) in dietary on hair growth and organs indexes were investigated. A total of 80 Kunming mice with a similar genetic background and weight were randomly divided into 0.12% (the control), 0.80%, 1.60%, and 2.40% Met treatments with five replicates per treatment, including two female and two male mice per treatment. The hair fibers, heart, liver, spleen, lungs, kidneys and thymus were collected in catagen and telogen, respectively. The results showed that hair diameters of mice were significantly decreased by adding 0.80%, 1.60% and 2.40% Met to diet (P＜0.05) in catagen and telogen. The length of hair in catagen and telogen were significantly reduced by 0.80% and 1.60% Met supplement (P＜0.05), but no changes were observed in hair diameters of the mice among four groups (P＞0.05). Compared with 0.12% Met group, spleen, lung, and renal indexes of mice from 0.80% and 1.60% Met groups were significantly improved (P＜0.05), but no significant effects of methionine were found on heart and thymus indexes (P＞0.05). Mice liver and renal indexes were significantly increased by 1.60% Met (P＜0.05), but no changes were observed in cardiac and spleen indexes (P＜0.05). In conclusion, the length and diameter of hair was significantly reduced, and spleen, lung and renal indexes were improved the by 0.80% and 1.60% Met in dietary.