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With superior hydraulic performance, the pressure compensating emitter (PCE) has extensive application in mountain and hill regions where the hydraulic pressure in irrigation systems often changes greatly. Because of the complicate structure, PCE design mechanism is still not clear. There’s a big difficulty in developing new types of PCE products even with high cost, which also makes it almost impossible to popularize PCE in China. The application and research status of PCE in both China and foreign countries was overviewed in order to supply a clear understanding to the readers. An improved development route for PCE was proposed on the base of combining several advanced techniques including numerical simulation, rapid prototyping (RP) and visualization experiment. Then the key problems involved in this route were discussed. And problems proposed in some early papers were solved. For the compensating mechanism is the key problem in PCE design and development, through part work of our team, it was pointed out that numerical simulation with fluid-structure interaction method, which provides us with pressure and velocity distribution, was an effective way to solve this problem.