An anchor point determination system for supporting dual connectivity, comprising: a Packet Co-operate Engine, PCE, a Master Node, MN, and a Secondary Node, SN, characterized in that, the PCE comprises: a memory and a processor, where the memory is adapted to store an anchor point determination program for supporting dual connectivity which, when executed by the processor, causes the PCE to: receive a bearer establishment request message sent by a Long Term Evolution, LTE, base station or a New Radio, NR, base station; and query a Packet Data Convergence Protocol, PDCP, entity corresponding to bearer information according to bearer information carried by the bearer establishment request message, and determining, according to whether the bearer establishment request message carries security information, whether the security information used by the PDCP entity corresponding to the bearer information changes; wherein: the MN and the SN are respectively connected to the PCE; an NR PDCP layer is deployed on the PCE; and the MN and the SN are respectively configured to select the same PCE as a PDCP anchor point for a User Equipment, UE, in response to the UE establishing dual connectivity with an LTE base station and an NR base station, wherein the LTE base station is the MN and the NR base station is the SN, or the NR base station is the MN and the LTE base station is the SN; and wherein a PDCP entity created for a radio bearer of the UE in the NR PDCP layer on the PCE is configured to use security information, which is derived from a security key of the MN, after the MN selects a PCE as the PDCP anchor point for the UE; and the PDCP entity is further configured to use the security information that remains unchanged after the SN selects the PCE as the PDCP anchor point for the UE. receive a bearer establishment request message sent by a Long Term Evolution, LTE, base station or a New Radio, NR, base station; and query a Packet Data Convergence Protocol, PDCP, entity corresponding to bearer information according to bearer information carried by the bearer establishment request message, and determining, according to whether the bearer establishment request message carries security information, whether the security information used by the PDCP entity corresponding to the bearer information changes; the MN and the SN are respectively connected to the PCE; an NR PDCP layer is deployed on the PCE; and the MN and the SN are respectively configured to select the same PCE as a PDCP anchor point for a User Equipment, UE, in response to the UE establishing dual connectivity with an LTE base station and an NR base station, wherein the LTE base station is the MN and the NR base station is the SN, or the NR base station is the MN and the LTE base station is the SN; and wherein a PDCP entity created for a radio bearer of the UE in the NR PDCP layer on the PCE is configured to use security information, which is derived from a security key of the MN, after the MN selects a PCE as the PDCP anchor point for the UE; and the PDCP entity is further configured to use the security information that remains unchanged after the SN selects the PCE as the PDCP anchor point for the UE.