Abstract: The study was conducted to examine the expression of GH mRNA in different tissues of mud carp by semi-quantitative RT-PCR and the effects of recombinant mud carp insulin-like growth factor-Ⅰ(rmcIGF-Ⅰ) on expression of GH in mud carp. GH mRNA detection result of brain of mud carp was positive, and the other tissues detections results were negative, including liver, kidney, spleen, muscle, intestine, gill, gonad, heart and skin. GH mRNA levels increased a little in brain in response to rmcIGF-Ⅰ, but the treated fish exhibited no obvious change in sera GH concentration following rmcIGF-Ⅰ injection.