Electric cell-substrate impedance sensing (ECIS) is a label-free and non-invasive technique for analyzing the activities and morphologies of cells. The ECIS sensors are able to measure the impedance spectroscopy of cells attaching on the sensor substrates. The cell activities and morphologies influence the measure impedance directly. Traditional toxicity analysis has complicated processes compared to biosensor-based analysis. In this study, the toxicity analysis was performed with biosensor based on ECIS technique. The experimental results show that the ECIS sensor is able to quickly distinguish the toxic and non-toxic substance.