Soil vapor extraction (SVE) is a cost-effective in-situ soil remediation technology being used widely abroad for removing volatile organic compounds (VOCs) from soil in the unsaturated zone. This paper reviews the development and status of the models of gas flow fields and the models of contaminants transport in SVE; describes the characteristics and applicable conditions of one-, two-, and three-dimensional models of gas flow fields and the models of contaminants transport with or without non-aqueous liquid; analyzes the effects of soil permeability, contaminants volatility, and air flow rate on SVE, using the models, summarizes results of the research; and discusses problems that needs immediate solution and prospect of the research and use of the models.