Considered as a health-harmful and climate-relevant pollutant, particulate matter (PM) has become a serious concern in China for recent years. Source apportionments of Chinese major cities show that fugitive dust can explain a large percentage of PM sources, while soil wind erosion contributes substantially to fugitive dust. Conservation tillage plays an important role in promoting crop growth and increasing production as well as in preventing wind erosion. Researches have been done to assess the benefits of conversation tillage in several perspectives respectively, whereas little concentrating on its comprehensive benefits. For better assessing the benefits of conservation tillage on eco-environmental, social and economic aspects comprehensively, a 3-tired index system was constructed based on field surveys, experiments and literatures, and tested in the case study of Tianjin. The assessment system included 3 indices of Grade-1 eco-environmental index, Grade-2 social index and Grade-3 economical index. Eco-environmental index included 4 sub-indices in Grade-2: soil physical-chemical properties, water retention ability of soil, soil resistance to wind erosion, and weeds and insects indices, respectively. Social index involved 2 sub-indices: agricultural mechanization rate, transfer of rural labor. The last 2 Grade -2 indices are input, and output subject to economical index. There were 19 more detailed indices in tire-3 to cover better range of this assessment. Three tillage modes utilized in Sujiayuan Village in Dagang District, Tianjin including traditional tillage and two kinds of conservation tillage (no-tillage with mulch and subsoiling) were analyzed to verify the feasibility of this index system. Fuzzy comprehensive evaluation (FCE) method was adopted and the weights of indices were calculated by standard deviation method in this assessment. The values of soil anti-erosion efficiency and soil particulate emission rate subject to soil resistance to wind erosion were calculated by a wind tunnel experiment conducted in Dagang district. A questionnaire survey was conducted in Sujiayuan Village to get values of agricultural mechanization rate and all the economical indices. An intensive literature research has been performed to get the rest of the indices’ values considering the similarity of climate and agrotype between Sujiayuan Village and places from where those values were obtained. According to the coverage of data collected, an eco-environment assessment with 11 indices involved and a comprehensive assessment with 19 indices included were conducted respectively. The results showed that conservation tillage performed more benefits than traditional tillage on the eco-environmental, social and economic aspects. Traditional tillage, no-tillage with mulch and subsoiling scored 0.182, 0.540, 0.875 in eco-environment assessment, respectively, and 0.279, 0.435, 0.584, in comprehensive assessment, respectively. At last, several problems were noted for the further study or utilization: 1) Due to the lack of knowledge about standards of each indices, it’s hard to define the detailed “rank” (or “evaluation value”) of specific index, which lead to the result that this assessment value only reflectes the relative superiority but not the practical gaps of these tillage modes; 2) Most values of indices were obtained from literatures; Despite the similarity of climate and agrotype, significant biases may potentially exist; and 3) Geographical condition varies among different areas, it is rational to utilize this assessment method with local conditions carefully considered. This study provides a useful tool for comprehensive assessment of conservation tillage.%保护性耕作是防治农田土壤风蚀起尘的重要技术方法之一，对于从源头上控制颗粒物污染有重要作用。为了综合评价保护性耕作技术的生态环境效益、社会效益和经济效益，该研究构建了一个包含3个一级评价指标、8个二级评价指标、19个三级评价指标的综合效益评价指标体系，并以天津市大港区苏家园村为例，对传统耕作、免耕覆盖、深松耕3种耕作方式下的生态、经济、社会及综合效益进行评价，以验证评价指标体系的可行性。结果表明：从生态环境效益方面来看，传统耕作＜免耕覆盖＜深松耕，其指标值分别为0.182、0.540、0.875；从综合效益来看，传统耕作＜深松耕＜免耕覆盖，其指标值分别为0.279、0.435、0.584。保护性耕作比传统耕作具有更高的生态环境和综合效益。该研究可为合理地评价保护性耕作综合效益提供参考，对发展保护性耕作起到良好的导向作用。
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