DNA methylation plays an important role in the regulation of gene expression during biological development and tissue differentiation in eukaryotes. A methylation sensitive amplification polymorphism(MSAP) including digestion, pre-selective amplification and selective amplification was optimized to compare the levels of DNA cytosine methylation at CCGG sites in muscle, gill and hemocyte from the wild populations and the selective breeding of Huanghai No. 1 of Fenneropenaeus chinensis, respectively. Significant differences in cytosine methylation levels among three tissues in two populations were detected. The average DNA methylation ratios in muscle, gill and hemocyte of the wild population were 23.1%, 22.3% and 19.7%, while those were 21.4%, 19.6%,and 18.9% in Huanghai No. 1, respectively. The DNA methylation levels of gill from the two populations were highly significant(P<0.01), the difference of muscle was significant(P<0.05), while in hemocyte, there were no significant differences(P>0.05). DNA polymorphic methylation of gill and hemocyte between the wild population and Huanghai No. 1 varies to some extent, while those of muscle kept in a balanced degree. Furthermore,polymorphic methylation was associated with demethylation and methylation of CCGG loci. DNA methylation plays an important role in the regulation of gene expression during biological development and tissue differentiation in eukaryotes. A methylation sensitive amplification polymorphism (MSAP) including digestion, pre-selective amplification and selective amplification was optimized to compare the levels of DNA cytosine methylation at CCGG sites in muscle, gill and hemocyte from the wild populations and the selective breeding of Huanghai No. 1 of Fenneropenaeus chinensis, respectively. Significant differences in cytosine methylation levels among three tissues in two populations were detected. The average DNA methylation ratios in muscle, gill and hemocyte of the wild population were 23.1%, 22.3% and 19.7%, while those were 21.4%, 19.6%, and 18.9% in Huanghai No. 1, respectively. The DNA methylation levels of gill from the two populations were highly significant (P <0.01), the difference of muscle was significant (P <0.05), while in hemocyte, there were no significant difference s (P> 0.05). DNA polymorphic methylation of gill and hemocyte between the wild population and Huanghai No. 1 varies to some extent, while those of muscle kept in a balanced degree. Yet, polymorphic methylation was associated with demethylation and methylation of CCGG loci.