Abstract: The integration of exogenous genes in transgenic plant genome are reviewed. Three integration patterns of exogenous genes included single-copy integration in one site, multiple-copy integration in one site and single-copy or multiple-copy integration in multiple sites. This review also analyses the influence of different integration patterns on the expression of exogenous genes, and discusses the mechanism of integration and the T-DNA integration model based on genomic DSB (double-strand breaks). In the end, the approaches studying different pattern of integration are introduced.