Abstract: 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.