A user authentication method using an authentication virtual code, the method comprising: receiving, by a server, the authentication virtual code, wherein the authentication virtual code is generated by an authentication virtual code generation function included in an authentication virtual code generation program based on authentication card data provided from an authentication card; wherein the authentication virtual code generation program is built or installed in an authentication virtual code generation device, and the authentication card data is provided by the authentication card to the authentication virtual code generation device through wireless communication, and the authentication virtual code is transmitted to the server from the authentication virtual code generation device; searching, by the server, for an authentication card storage location, at which the authentication card is registered in the server, by a storage location search algorithm based on the authentication virtual code, wherein the storage location search algorithm is matched with the authentication virtual code generation function and searches for the authentication card storage location based on at least one detailed code in the authentication virtual code; identifying, by the server, a user by extracting user information stored at the corresponding location; verifying, by the server, the authentication virtual code based on a time point at which the authentication virtual code is received; and approving, by the server, user authentication, wherein the verifying of the authentication virtual code includes: comparing, by the server, a time point, at which the received authentication virtual code is received, with a time point, at which the authentication virtual code generated by the authentication virtual code generation function is generated; and when the generation time point is included within an error range from the reception time point, determining that the received authentication virtual code is a normal code. receiving, by a server, the authentication virtual code, wherein the authentication virtual code is generated by an authentication virtual code generation function included in an authentication virtual code generation program based on authentication card data provided from an authentication card; wherein the authentication virtual code generation program is built or installed in an authentication virtual code generation device, and the authentication card data is provided by the authentication card to the authentication virtual code generation device through wireless communication, and the authentication virtual code is transmitted to the server from the authentication virtual code generation device; searching, by the server, for an authentication card storage location, at which the authentication card is registered in the server, by a storage location search algorithm based on the authentication virtual code, wherein the storage location search algorithm is matched with the authentication virtual code generation function and searches for the authentication card storage location based on at least one detailed code in the authentication virtual code; identifying, by the server, a user by extracting user information stored at the corresponding location; verifying, by the server, the authentication virtual code based on a time point at which the authentication virtual code is received; and approving, by the server, user authentication, wherein the verifying of the authentication virtual code includes: comparing, by the server, a time point, at which the received authentication virtual code is received, with a time point, at which the authentication virtual code generated by the authentication virtual code generation function is generated; and when the generation time point is included within an error range from the reception time point, determining that the received authentication virtual code is a normal code. comparing, by the server, a time point, at which the received authentication virtual code is received, with a time point, at which the authentication virtual code generated by the authentication virtual code generation function is generated; and when the generation time point is included within an error range from the reception time point, determining that the received authentication virtual code is a normal code.