Abstract: According to the performance of 6110 ZL turbocharged diesel engine with intercooler, the mathematics model of the diesel was set up, and a method and related formula to calculate air inlet final state were put forward. The calculating method of half turbine leaf was put forward, so it was possible that the single inlet turbine unary flow analysis method could be applied to the no leaf turbine. The simulated calculation software for 6110 ZL turbocharged diesel engine with intercooler was developed.