Using 130nm CMOS technology, an eight metal layer process, this thesis is aimed at developing an integrated circuit to find bioimpedance using multi-frequency bioelectrical impedance analysis technique. By injecting current at multiple frequencies into a biological subject and measuring the voltage response of the subject, and the ratio of the response to excitation would aid in finding the bioimpedance of the biological subject. A low power, high differential gain operational amplifier with high CMRR is designed to develop current sources, voltage measuring circuits and post-processing circuits. Transient and DC simulations have been done to validate the concept of determination of bioimpedance. Layouts have been designed and the chip is fabricated and tested for results.