A method of cell selection for a user equipment (UE) is provided. If a hierarchical cell structure (HCS) is used in a serving cell of the UE, a ranking procedure is performed in a first manner if the UE has low mobility, and the ranking procedure is performed if in a second manner the UE has high mobility. When the UE has low mobility, the ranking procedure is performed for all measured cells that have a highest HCS priority among those cells that fulfill a criterion S and a criterion H≧0, or the ranking procedure is performed for all measured cells regardless of HCS priorities if no cell fulfills the criterion S and the criterion H≧0. When the UE has high mobility, the ranking procedure is performed for all measured cells, and if there are cells with lower HCS priority than the serving cell that fulfills the criterion S and the criterion H≧0, the ranking procedure is performed for all cells that have the highest HCS priority. Otherwise, if there are cells that fulfill the criterion S and the criterion H≧0 with a HCS priority that is higher than or equal to the HCS priority of the serving cell, then the ranking procedure is performed for all cells that have the lowest HCS priority, else, the ranking procedure is performed for all cells regardless of HCS priorities.