Provided are a cell selection/re-selection method for an inter-frequency sidelink operation executed by a terminal in a wireless communication system, and a terminal using the method. The method is characterized by determining whether cell selection/re-selection parameters which can be applied to a non-serving frequency to execute a sidelink operation have been configured and received; and when the cell selection/re-selection parameters have been configured and received, performing an evaluation for the cell selection/reselection or ranking of a cell in the non-serving frequency by using the cell selection/re-selection parameters.