In this paper,we build the reaction function about fisca1 expenditure growth rate on other macroeconomic variables,and measure two kinds of uncertainties of fiscal expenditure growth rate respectively which are led by endogenous and exogenous shocks,by time-varying model and switch regime mode1.Statistics test shows only time-varying model and switch regime union model can fit all uncertainties of fiscal expenditure growth rate.W e study the impact of these two uncertainties on trend component of household consumption growth rate.The empirical results show that the uncertainty of fiscal expenditure growth rate led by endogenous and exogenous shocks respectively has negative and positive effect on household consumption of China.