Micro rubber pneumatic actuators have attracted in medical and biotechnology fields, especially they have been expected for minimally invasive surgery and handling biological cells because of high safety caused by low mechanical impedance. Actually some micro rubber pneumatic actuators have been developed in several laboratories. However at present, almost no actuators could realize simple structure, easy fabrication and large displacement enough to holding objects by one actuator. In this paper, an actuator, named “Nematode Actuator”, having large deformation with simple structure is developed by nonlinear FEM (Finite Element Method), and fabrication process is simplified using rubber bonding technology with excimer lamp and machining. Nematode actuator realized remarkably large bending motion as like a nematode in two directions only one air tube using positive and negative pressure.