Cellular microenvironment, such as physical and chemical properties in the neighborhood, could strongly affect cellular activities, such as morphology, proliferation, differentiation. One powerful tool to control the microenvironment and affect cellular behaviors is microfluidic device, which is frequently developed based on PDMS. By controlling PDMS surface structures at different scales, we studied the cellular responses to the mechanical cues after a long term culture in term of adhesion, proliferation, differentiation for MSC. On the other hand, PDMS structures with various curvatures and angles were designed and fabricated to study responses of neurons, such as neurite morphology as well the formation of cultured network.