With a view to the key practical techniques for dimethyl ether (DME) engine, the strategies of anti-wear and leakage were discussed for the DME fuel injection system. In order to solve the wear and leak problems which have occurred in needle couple due to low lubricity of DME, wear self-compensation nozzle and independent lubrication nozzle were developed to replace the traditional diesel nozzles. Under AMESim Modeling Environment, the injection characteristics of wear self-compensation nozzle, as well as working process and leakage characteristics of independent lubrication nozzle were analyzed meanwhile the needle lift experiment was conducted. The results have shown that, the working features of both types of nozzles are suitable for the injection system of DME engine, the characteristics of injection, atomization and reliability need to be further investigated for the wear self-compensation nozzle, so the independent lubrication nozzle is more reliable and practical now. The research plays a positive role in motivating the practical application of DME engine.