Abstract: Cell analysis based on electrical impedance is a label-free and non-invasive technique, which has been widely used to analyze and identify cell characteristics in various applications, such as tissue culture, cell growth and viability detection. Microfluidic（also known as "Lab on a Chip "） technology can integrate analytical processes involving sample preparation, operation and impedance-based detection into a single chip, minimizing the size and weight of the system. In this paper, a simple microfluidic impedance detection system is built, and a microfluidic impedance chip is designed. The induction signal is amplified by a self-made lock-in amplifier and processed by self-developed algorithm on MATLAB, and the characteristic parameters are extracted and analyzed. Different particles of similar size can be distinguished according to electrical differences, which has the advantages of low cost, easy integration and non-labeling, and can be further used for on-site cell real-time detection in the future.