Vegetation restoration in the water level fluctuation zone (WLFZ) is vital for maintaining the health and stability of the Three Gorges Reservoir. Many technical methods (i.e. planted species and concrete-engineered methods) of vegetation restoration were performed in this zone. However, these methods are not suitable for the WLFZ with repeated collapse and soil erosion. To evaluate the potential of ecological-bag (eco-bag) slope protection technology, an effective method for slope fixation and re-greening in various environments, population characteristics (density, morphological traits and biomass) of Cynodon dactylon, and physicochemical indicators of soil on/in the eco-bag and around the eco-bag stacking (upper and left sides) at two plots (Shuanglong and Wuxia) in Wushan County of Chongqing Municipality were investigated after 7-year of experimental setup. The results showed that population density and aboveground biomass at two plots were no significant differences between on the eco-bag and around the eco-bag stacking. However, morphological traits and root biomass varied with different plots and positions. In Shuanglong plot, length and inter-node length of C. dactylon on the eco-bag decreased by 23.9% and 22.6% than those around the upper side of the eco-bag stacking, respectively (P<0.05). Root biomass of 0-5 cm in the eco-bag was 75.7% more than around the upper side of the eco-bag stacking (P<0.05), while was 11.8% lower than around the left side of the eco-bag stacking. And root biomass of 5-15 cm in the eco-bag were lower than around the eco-bag stacking, with proportion of 91.6%-96.9%. In Wuxia plot, root biomass of 0-20 cm in the eco-bag increased by 20.0%-138.7% than around the eco-bag stacking, while there were no significant differences in morphological traits and aboveground biomass. Additionally, soil chemical indicators also changed with different plots and positions. In Shuanglong plot, soil total nitrogen and available nitrogen in eco-bag was significantly lower than that around the eco-bag stacking, with proportion of 11.9%-40.9%; while soil available potassium increased by 18.3% (upper side) and 34.1% (left side), respectively (P<0.05). In Wuxia plot, soil pH and total nitrogen in the eco-bag decreased by 1.4% and 27.9% than around the upper side of the eco-bag stacking, respectively, but total potassium increased by 6.1% (P<0.05); soil total potassium and available potassium were 8.1% and 24.9% lower than around the left side of the eco-bag stacking, respectively (P<0.05). Further, not all significant relationships were found between population density, morphological traits, above- and underground biomass and soil physicochemical indicators. In total, population characteristics of C. dactylon and physicochemical indicators of soil had no obvious differences between on/in the eco-bag and around the eco-bag stacking. C. dactylon, one of species with resistance to flood, drought and poor fertility, had stronger root and grew well on the eco-bag. On the other hand, eco-bag is permeable to water but no to soil, implying some retention ability for fertility. Thus, eco-bag slope protection technology has huge potential for vegetation restoration in the WLFZ of the Three Gorges Reservoir.