A method for selecting transmission resource, applied to a network device, characterized by comprising: transmitting a duplication configuration to a user equipment, UE, wherein the duplication configuration is used for determining, by the UE, whether to perform duplication, and is used for at least one transmission resource, which is used when transmitting data, configured for the UE; wherein the duplication configuration comprises an index of at least one transmission resource used for transmitting data and/or duplicating data; wherein the duplication configuration further comprises at least one of the following: an initial state of a duplication mode and a number of pieces of duplicated data corresponding to the initial state; wherein the duplication configuration further comprises: a logical channel when the duplication mode of the bearer for performing duplication configured for the UE is in a deactivation state, wherein the method further comprises: in response to a duplication state being needed to be modified, transmitting second indication information to the UE through one of RRC, DCI and MAC CE, wherein the second indication information is used for indicating a bearer for which the UE needs to modify the duplication state and a number of pieces of duplicated data corresponding to the bearer; wherein the method further comprises: receiving transmission resource selection information fed back by the UE through the MAC CE or a physical layer signaling; wherein the transmission resource selection information comprises at least one of the following: a carrier index selected by the UE, an RLC entity index selected by the UE, a logical channel index selected by the UE, a cell group index selected by the UE, and a CG index selected by the UE; wherein the method further comprises: transmitting third indication information to the UE, wherein the third indication information comprises an index of at least one transmission resource that can be used by the bearer for which the duplication state needs to be modified. transmitting a duplication configuration to a user equipment, UE, wherein the duplication configuration is used for determining, by the UE, whether to perform duplication, and is used for at least one transmission resource, which is used when transmitting data, configured for the UE; wherein the duplication configuration comprises an index of at least one transmission resource used for transmitting data and/or duplicating data; wherein the duplication configuration further comprises at least one of the following: an initial state of a duplication mode and a number of pieces of duplicated data corresponding to the initial state; wherein the duplication configuration further comprises: a logical channel when the duplication mode of the bearer for performing duplication configured for the UE is in a deactivation state, in response to a duplication state being needed to be modified, transmitting second indication information to the UE through one of RRC, DCI and MAC CE, wherein the second indication information is used for indicating a bearer for which the UE needs to modify the duplication state and a number of pieces of duplicated data corresponding to the bearer; receiving transmission resource selection information fed back by the UE through the MAC CE or a physical layer signaling; wherein the transmission resource selection information comprises at least one of the following: a carrier index selected by the UE, an RLC entity index selected by the UE, a logical channel index selected by the UE, a cell group index selected by the UE, and a CG index selected by the UE;