Abstract: In this study, we used real-time PCR to investigate the effects of fasting and re-feeding on the expression of two MSTN genes in large yellow croaker (Larimichthys crocea). The results showed that during the 35-day fasting treatment, the expression of MSTN-1 and MSTN-2 in skeletal muscles firstly increased and then decreased, and their expressions perked on the 21st and the 28th day respectively. The expressions were down-regulated during the re-feeding period. The expression patterns of the two MSTNs were different in the brain, although they both reached the lowest level on the 35th day and then increased after re-feeding. In the spleen the expressions of MSTN-1 and MSTN-2 reached to the highest levels on the 28th and the 21st days respectively, and both declined after the re-feeding. In kidney the expression patterns of the two genes were similar, and they both reached the lowest on the 21st day after fasting followed by an increase. The expression of MSTN-1 and MSTN-2 in the intestine decreased significantly on the 14th and the 7th day respectively, and then peaked on the 28th day. In the liver, the expression of MSTN-1 and MSTN-2 decreased sharply on the 21st day and then increased. The expressions of both genes were up-regulated after re-feeding. Our findings suggested that the functions of the two MSTN genes might be various in different tissues.