Dear editor,rnWireless powered communication network(WPCN)is a wireless network where user devices are powered wirelessly by harvesting radio frequency(RF)signals transmitted by dedicated power stations or nearby power sources[1].WPCN is attractive for wireless networks with low-power user devices,such as wireless sensor networks[2]and backscatter networks[3].Meanwhile,physical layer security(PLS)is a technique that can guarantee secure communica-tion from the aspect of the physical layer by exploring the randomness of physical channels[4,5].PLS in WPCN is different from that in non-WPCN mainly owing to the re-quirement of balancing between the RF energy harvesting and secure information transmission in WPCN[6,7].Exist-ing studies on PLS in WPCN considered that the eavesdrop-pers are not legitimate users in the WPCN.For the situation when the legitimate user in the WPCN is interested in other user\'s information,the legitimate user can be treated as an eavesdropper for other users.Such a situation is more dif-ficult to handle because each user has to balance between transmitting their own information and eavesdropping on other users.