Research on the biotechnology field using micro devices has been carried out variously, and we focus on mechanical stimulation to biological samples in this paper. However, dedicated devices such as microprobes tend to be expensive and are not easy to fabricate. Therefore, we propose a device which can stimulate the biological sample using PDMS structure deformation by pressure control, and can easily fabricate it. By measuring the relationship between inlet pressure and PDMS deformation, we confirmed the stability of behavior of the proposed device. Furthermore, using the proposed device, an experiment system for roots of broccoli sprout is constructed.