Abstract: A active filter network is designed,and a systematic design method for current-mode second-order filter based on CCⅢ is presented.The systematic design formula derivation is performed.Its circuit consists of a CCⅢ+ and four passive components.It can realize second-order low-pass,high-pass,band-pass filtering functions.The proposed circuits have very low passive and active sensitivities,and its port network circuit is simple structure and its structure is changeless,and its circuit can be easily cascaded to produce higher-order filter.The circuit is simulation in PSPICE,simulation results show that design theory is correct and design method is feasible.