Epigenetic modifications play a essential role in regulation of genes expression and maturation of germ cells, growth and development of embryo. Epigenetic modification includes covalent modification of chromatin mainly genomic DNA methylation designated as imprinting. Correct methylation pattern can be responsible for successful embryonic growth and the healthy development of the offspring in postnatal life. In primordial germ cells, inherited imprinted genes lose their methylation imprints, and de novo monoallelic sex-specific methylation subsequently takes place during gametogenesis. After fertilization the methylation pattern is erased and de novo established. We decided to present the significance of DNA methylation in maturation of human germ cells, embryonic development.