Because of difficult quantification on socioeconomic benefit in China’s highway project post evaluation, GM(1,1) Model is used to simulate and predicate socioeconomic benefit for an unit with a highway project or without a highway project, the difference of predicative values between the two can approximately estimate the socioeconomic benefit resulted from a highway project. Taking Yuhe Highway as an example, this paper simulates and predicates GDP of the units along the Highway and the results show that Yuhe Highway construction brings obvious change of socioeconomic development of the units along the Highway.