A methodology to synthesise continous-time current-mode filters using CMOS OTAs is presented. Second-order CMOS-OTA current fllters are systematically generated from the simulation of signal flow graph for a general biquadratic function .The non-ideal effects in high frequency compensation frequency characteristic of OTA-C filters are analyzed. A simple high off frequency method is discussed. Finally, A 4th-order Butterworth lowpasss filter with 1MHz cut and simulated with PSPICE program.