To control the velocity and one-way flow of fluid in a micro-fluidic system, a novel passive micro-valve was designed base on Micro-electrical-mechanical System(MEMS) technology. By drawing lessons from a human heart valve structure, the deflections and stresses of a valve membrane under different pressures were analyzed with ANSYS by using SU-8 as the passive micro-valve structural materials, then the thickness of the valve membrane was optimized. The valve was fabricated with integrated processing of MEMS technique, so that the process technology for the valve membrane was determined. The performance of the passive valve was tested using deionized water as media and the forward flow velocities obtained are 1.66 ml/min for type A and 1.35 ml/min for type B under a forward pressure of 11.7 kPa. The tested analyzing data indicate that the designed passive valve has the potentiality of linear control, which means that the passive micro-valve made by SU-8 has not only better performance but also better bio-compatibility and can extend the applications of passive micro-valves.