The investigation, analysis,pot tests and field experiments were conducted to deal with the feasibility to build pollution free vegetable base in latent pollution area surrounding metropolis,based on Caoshang area in Chongqing.The problems of base construction were put forward by means of systematic step analysis.The ecological planning and construction of Caoshang base were suggested at the end of the paper. The investigation, analysis, pot tests and field experiments were conducted to deal with the feasibility to build pollution free vegetable base in latent pollution area surrounding metropolis, based on Caoshang area in Chongqing. The problems of base construction were put forward by means of systematic step analysis. ecological planning and construction of Caoshang base were suggested at the end of the paper.