This paper analyzes the reason why there is a error in an optimized GM (1,1) based on connotation expression, though it has improved the modeling precision greatly. Then put forward a solution method for this reason, and obtain a new GM (1,1) model which improves the model precision further. The new model has been proven strictly to have the property of white exponential law coincident, so it not only to be suitable for the low growth sequence, but also suitable for the high growth sequence. Through simulation to a large number of data and comparing with the original GM (1,1) model and the optimized GM (1,1) model based on connotation expression, we discovered that the new optimized model in this paper has a very high simulation and forecasting precision.