A semiconductor device is provided. The semiconductor device includes: a processor core which processes program data; a first memory mounted on the same semiconductor chip as the processor core; a second memory including an MRAM cell having a first MTJ (Magnetic Tunnel Junction) structure; a third memory including an MRAM cell having a second MTJ structure different from the first MTJ structure, wherein the processor core selectively stores the program data in one of the first memory, the second memory and the third memory, on the basis of an attribute of the program data.