Based on sensitivity of fuel physicochemical property to temperature,in order to study the effects of fuel injection temperature on spray and combustion performance of diesel engine, commercial CFD software STAR-CD is used to simulate the spray and combustion processes of diesel engine with heating fuel spray. Through compared with experimental results, calculation models are proved to be validity. The effects of different fuel injection temperatures on in–cylinder air motion, temperature field and exhaust emissions are researched in the CA6DL1-30 diesel engine. The results show that there is a valid temperature range for fuel injection in diesel engine. And it’s possible to implement Low NOx Combustion with heating fuel spray.