Somatic cell nuclear transfer (SCNT, Somatic cloning) has been succeeded in some species, but the low cloning efficiency limits its application in many areas, including medicine industry, therapeutic cloning and the propagation of rare animals. In somatic cell nuclear transfer process, the donor nucleus requires epigenetic reprogramming to a totipotent ground state. Although molecular events within hours of nuclear transfer determine the fate of cloned embryos, it is disappointing that so little is known about these events during the early development of cloned embryos. Genomic imprinting is the differential expression of a gene based upon parental inheritance. DNA methylation is a known regulator of major genomic imprinting, and many imprinted genes are associated with DMRs that play a role in regulating their allele specific expression. Mash2 is an imprinted gene that plays important role in embryo development and organogenesis. Aberrations were often observed in the lungs of most deceased cloned calves died around birth. In an effort to determine whether the DNA methylation reprogramming of Mash2 is efficient in somatic cloning animals, the DNA methylation status of Mash2 was analyzed in lungs of deceased somatic cloning bovines that died within 48 h of birth using bisulfite sequencing analysis. The results demonstrated that cloned bovines showed significantly lower DNA methylation of Mash2 than controls (P < 0.05), and both showed low methylation (20.04% and 5.55%)，and the percentage of overall mCpG in 9C5 was only 0.4%；the types of methylation patterns were five in 9N3 and one in 9N4，while only one type were found in cloned cow．The abnormal DNA methylation of Mash2 may contribute to the lung development defects and the low efficiency of somatic cloning.