A semiconductor device includes: a spin torque written in-plane magnetization magnetoresistive element, placed over the main surface of a semiconductor substrate, whose magnetization state can be changed according to the direction of a current flow; and a first wiring electrically coupled with the magnetoresistive element and extended toward the direction along the main surface. The aspect ratio of the magnetoresistive element as viewed in a plane is a value other than 1. In a memory cell area where multiple memory cells in which the magnetoresistive element and a switching element are electrically coupled with each other are arranged, the following measure is taken: multiple magnetoresistive elements adjoining to each other in the direction of length of each magnetoresistive element as viewed in a plane are so arranged that they are not on an identical straight line extended in the direction of length.