By using provincial panel data model of 1988-2010 years, this article provides an analysis framework based on fiscal decentralization, government competition and expenditure for agriculture. The results show that fiscal decentralization has promoted local government fiscal expenditure for agriculture, but crossing time and regional differences are significant. The cross terms of government competition and fiscal decentralization have hampered fiscal expenditure for agriculture, and in the East is more remarkable. The regression results remain robust when joining variables. In addition, the local government fiscal expenditure for agriculture has apparent cumulative effect. The expenditure is drove by macroscopical economic policy significantly, but the effect is reducing.