A transposition operation device includes: a register group storing a matrix of data such that elements are readable one at a time; an output data rearrangement unit rearranging elements in each row of the matrix so that elements in a same column of the matrix are in different columns of the matrix after rearrangement; a register access unit writing the matrix after rearrangement to the register group and reading the elements in the same column by using column position information indicating positions in the register group at which the elements in the same column are stored; an input data rearrangement unit rearranging the read elements; an operation unit performing an operation on the rearranged elements; and a transposition control unit generating rearrangement information and the column position information to control rearrangement, and performs transposition at high speed by performing rearrangement at the time of storing/reading data in/from the register group.