In order to quickly calibrate SCR controller, space-falling experiment design was applied to get 130 optimization operation points while developing SCR system for a type of diesel engine, which reduced the experimental workload for two-thirds. The target diesel engine emission model and SCR catalyst model were developed by using neural network based on diesel emission characteristic experimental database and catalyst characteristic experimental database. Multi-objective optimization arithmetic was applied to gain urea dosing map based on SCR catalyst model. ESC (Europe steady cycle) experiment validated that the precision of urea dosing map satisfied the requirement of SCR control.