The invention discloses an ecological slope protecting system for infiltration of accumulated water of loess slope small-section cave dwellings in a foundation. The ecological slope protecting systemcomprises a water channel located in the top of a slope, and a plurality of sand wells a are evenly distributed at the channel bottom of the water channel; a plurality of steps which are mutually connected are further distributed on the slope, the multiple cave dwellings are evenly distributed on each layer of steps, and sand wells b are arranged on the steps in front of each cave dwelling correspondingly and connected to the inner wall of the cave dwelling the next layer through water transferring pipes; the sand wells are connected to the inner walls of the cave dwelling located at the uppermost layer through slope body water transferring pipes; and the interiors of all the cave dwellings and the top of the slope are further provided with greening units correspondingly. According to theecological slope protecting system, the cave dwellings are excavated in the loess slope face, plants are planted through the slope accumulated water, natural resources can be utilized, and a good ecological recovery effect can be achieved; and the ecological slope protecting system and traditional slope face engineering protection measures form a slope engineering plant protection system jointly,and very good practical value is achieved.