Abstract: To understand the gene-flow rules of transgenic rapeseed, we first constructed a rapeseed gene-flow topological graph and analyzed its structural characteristics on the basis of data of normal rapeseed hybridization with Cruciferae. The node degree of the network follows the power-law distribution and has scale-free properties. Then, using the 2 indices of standard structure entropy and network efficiency, we analyzed the network robustness according to random attacks and intentional attacks. The gene-flow network is robust against random failures of nodes but fragile to intentional attacks with removal of no more than 10% nodes. Finally, we analyzed the subgroup and structural position by the UCINET software and found 298 nodes, namely 22 kinds of Cruciferae plants, divided into 2 subgroups and 5 structural positions; Brassica napus played a key role in subgroups and structural position. These results provide a new approach for transgenic rapeseed gene-flow research and gives some references for reasonable cultivation measures of transgenic rapeseed.