Dear editor,rnRadio frequency (RF) energy harvesting is a technology that enables harvesting energy from RF signals,and the wireless powered communication network (WPCN) is a new type of wireless network,where devices are powered by RF energy harvesting[1,2].Meanwhile,physical layer security (PLS)is a technique to ensure communication security from the aspect of the physical layer,and how to effectively surveil wireless information transmission is an important research topic in PLS[3,4].Different from traditional PLS where eavesdropping is treated as a threat to legitimate communi-cation[5],wireless information surveillance treats suspicious communication of malicious users as a threat to public safety and eavesdrops the suspicious communication.The existing studies on wireless information surveillance with RF energy harvesting include[6-8]and they considered only very sim-ple point-to-point suspicious networks with RF energy har-vesting.For more complex suspicious networks with mul-tiple suspicious links based on RF energy harvesting,the tradeoff of eavesdropping performances among different sus-picious links must be considered.However,such research topics have not been well investigated yet in the existing literature.