提出一种计算mdct的快速算法，并分析了算法的计算复杂度，与利用fft计算的算法相比，本算法的计算复杂度降低了约一半。最后给出该算法的计算机仿真结果。-Presents a fast algorithm for calculating mdct and analyze the computational complexity of the algorithm, and the use of fft calculation algorithm, this algorithm reduces the computational complexity by about half. Finally, the results of computer simulation of the algorithm.