There is provided a semiconductor device including regular cells (16) disposed in a regular sector (10) and connected to a word line (14), and a plurality of reference cells (26) used in reading data from the regular cells (10), wherein one of the reference cells is selected based on a word line distance associated with a regular cell (16) from which data is read. In accordance with the present invention, it is possible to reduce the difference in delay times in the outputs to the sensing amplifier (30) from the regular cell (16) and the reference cell (26), by selecting one of a plurality of reference cells (26) in response to the word line distance of the regular cell from which data is read. It is therefore possible to provide a semiconductor device in which the chip area can be reduced and the sensing operation can be accelerated.