Cultivating more than 170.3 million hectares of GM products in more than 28 countries and consumption of GM products in hundreds of countries, do not block opposition of some apparently environmentalist or Human health groups. One of the concerns expressed by these groups is probability of unintended effects due to insertion of transgene in a region of host genome which may be critical to the quality of the product. Toevaluate theresult ofinsertionof a transgene into the genomeknowing the sequence surrounding the integrationsitecan be useful. Althoughthe Identification of DNA sequences flanking transgene insertions site is not consider as a necessary steps of biosafetyriskassessment, butGM productsmanufacturersandresearchers in thisfield do this analysis voluntary and to create more confidence in consumers. Various methodshave been proposedto determination of DNA sequences adjacent to transgene, each method has advantages and special complexities.This paper review and analysis the procedures. These techniquesincludemethodsbased cloning andPCR. Cloning despite high accuracy, less has been used due to time-consuming. In contrast, PCR-based methods are rapid and cheap and a large number of these methods have been developed in recent years,which are divided into three main groups: inverse PCR, ligation/adaptor mediated PCR and primer-based methods.