In order to protect ultra-precision machining, precision measuring instruments and other high-tech equipment against environmental vibration, the vibration isolation performance of centralized control and distributed control in six DOF is investigated and compared for a four-legged active vibration isolation platform with symmetrical layout. In this paper, a six DOF rigid body model and vibration transfer model is constructed, and the centralized control scheme and decentralized control scheme are given respectively, and the corresponding decoupling condition and vibration transfer function are studied. Furthermore, through the vibration transmission analysis, the parameter adjustment method of vibration frequency and damping coefficient in six DOF is derived. The effectiveness of the two control methods is verified by simulation experiment. The theoretical analysis and simulation results show that the centralized control can independently adjust the six DOF isolation performances, the isolation damping and stiffness in three linear-degree of freedom directions can be changed independently through 8 control gains, and independently adjust the isolation frequency of three angular-degree of freedom directions through other 6 control gains, so that the vibration rate power spectrum can be significantly reduced by 50% to more than 90%. Decentralized control is independent for each support foot, which is easier to debug and combine applications. It can independently adjust the isolation frequency and damping in three linear-degree of freedom directions through three groups of 6 gains, and the vibration isolation performance in three angular-degree of freedom directions can be adjusted through cross-correlation with linear-degree of freedom, so as to achieve a vibration rate power spectrum attenuation by more than 90%.