Some properties of living cells are associated with cell adhesion and cell spreading process. Traditional way to monitor cells' morphological changes is usually the use of optical microscope. Biosensors provide an alternative to automatically monitor cell adhesion and spreading process. This study utilized microelectrodes array based impedance biosensors to record cells attachment and differentiation via changes of impedance. The results were confirmed with the images of optical microscope. Based on the electrical model proposed, cell adhesion and differentiation can be clearly identified without any additional biochemical tests.