Abstract—The mathematical model of uniform circular array was established and some simulation experiment systems were constructed. The direction finding efficiency of MUSIC based on uniform circular array was studied by simulation experiments. Then MUSIC based on uniform circular array was compared with MUSIC based on uniform linear array. The conclusions are as following. Two kinds of MUSIC can find the directions of independent signals and their DF accuracy is close. They all cannot find the directions of coherent signals. The advantage of MUSIC based on UCA: the array size is smaller; it is easier to increase antenna to improve the DF accuracy; the angle distinguishing ability of signals is higher; there is neither image vagueness nor aperture vagueness. The weakness of MUSIC based on UCA: it cannot eliminate the coherence of coherent signals; the ability to find the direction of weak signal is poorer.