The disclosure provides a matrix transposing circuit for outputting a transposed N×N matrix. The matrix transposing circuit includes: an input resister array with m×N array; a memory having b storage blocks; an output register array with N×m array. N, m, n, b are integer in power of 2, N can be completely divided by m and n, and N=n×m×b. The matrix is divided into multiple sub-matrixes with m×n array to form Y matrix. Each of sub-matrixes is correspondingly stored to the b storage blocks. The input resister array has a first shifting direction to receive entry data and a second shifting direction to output data to the b storage blocks. The output resister array has a first shifting direction to read data from the b storage blocks and a second shifting direction to output the transposed matrix.