A resource selection method performed by a user equipment, UE, the method comprising: comparing a reference signal received power, RSRP, of a channel with a preset received power threshold if a maximum number of demodulation reference signal, DMRS, ports corresponding to a physical sidelink shared channel, PSSCH, is at least two; wherein the channel is a PSSCH scheduled by a physical sidelink control channel, PSCCH, sensed by the UE; and the maximum number of DMRS ports is a maximum number of DMRS ports of the PSSCH scheduled by the PSCCH sensed by the UE, or a maximum number of DMRS ports of a PSSCH transmitted in a resource pool used by the UE; determining whether to perform resource exclusion in a resource selection window of the UE according to a comparison result obtained from comparing the RSRP of the channel with the preset received power threshold in the comparing step; and performing an initial transmission or retransmission in the sidelink using one or more resources in available remaining resources of the resource selection window after the resource exclusion is performed; wherein the maximum number of DMRS ports corresponding to the PSSCH being at least two, comprises: the resource pool used by the UE is configured for: comparing an RSRP of a PSSCH scheduled by a sensed PSCCH with the received power threshold; and a field corresponding to a number of DMRS ports in sidelink control information, SCI, transmitted in the PSCCH sensed by the UE is a preset value; wherein the comparing the RSRP of the channel with the preset received power threshold comprises: comparing a sum of RSRPs of respective DMRS ports of a PSSCH with the received power threshold; wherein the PSSCH is the PSSCH scheduled by the PSCCH sensed by the UE. comparing a reference signal received power, RSRP, of a channel with a preset received power threshold if a maximum number of demodulation reference signal, DMRS, ports corresponding to a physical sidelink shared channel, PSSCH, is at least two; wherein the channel is a PSSCH scheduled by a physical sidelink control channel, PSCCH, sensed by the UE; and the maximum number of DMRS ports is a maximum number of DMRS ports of the PSSCH scheduled by the PSCCH sensed by the UE, or a maximum number of DMRS ports of a PSSCH transmitted in a resource pool used by the UE; determining whether to perform resource exclusion in a resource selection window of the UE according to a comparison result obtained from comparing the RSRP of the channel with the preset received power threshold in the comparing step; and performing an initial transmission or retransmission in the sidelink using one or more resources in available remaining resources of the resource selection window after the resource exclusion is performed; wherein the maximum number of DMRS ports corresponding to the PSSCH being at least two, comprises: the resource pool used by the UE is configured for: comparing an RSRP of a PSSCH scheduled by a sensed PSCCH with the received power threshold; and a field corresponding to a number of DMRS ports in sidelink control information, SCI, transmitted in the PSCCH sensed by the UE is a preset value; wherein the comparing the RSRP of the channel with the preset received power threshold comprises: comparing a sum of RSRPs of respective DMRS ports of a PSSCH with the received power threshold; wherein the PSSCH is the PSSCH scheduled by the PSCCH sensed by the UE. the resource pool used by the UE is configured for: comparing an RSRP of a PSSCH scheduled by a sensed PSCCH with the received power threshold; and a field corresponding to a number of DMRS ports in sidelink control information, SCI, transmitted in the PSCCH sensed by the UE is a preset value; wherein the comparing the RSRP of the channel with the preset received power threshold comprises: comparing a sum of RSRPs of respective DMRS ports of a PSSCH with the received power threshold; wherein the PSSCH is the PSSCH scheduled by the PSCCH sensed by the UE.