Farmland abandonment is the result of comprehensive effects by multiple driving forces. Ecological environment impact by farmland abandonment has its particularity in different regions. Aiming at the current phenomenon of farmland abandonment in the southwest karst areas, this paper summarizes the current research progress and future research prospects on the ecological environment impact of farmland abandonment in karst areas of the southwest China. By summarizing existing studies on ecological and environmental effects by farmland abandonment, it revealed that:(1) the opportunity cost of farming increased. The implicit abandonment being mainly characterized by extensive management may be the potential driving force for modern development of rocky desertification; (2) The soil heterogeneity in the karst areas determines the landscape homogeneity at the plot scale or the landscape heterogeneity at the regional scale after a farmland abandoned; (3) Vegetation restoration after abandonment of farmland in karst areas can improve soil structure, maintain soil moisture and promote soil nutrient restoration to a certain extent; (4) Soil erosion intensifies in early stage of abandonment, and soil erosion will be prevented and controlled by restoration of vegetation in later stage of abandonment; (5) The restoration of vegetation on abandoned farmland enhances the effects of plant carbon sink, soil carbon sink and karst carbon sink in karst areas. In the future, the specific impact of implicit abandonment on ecological environment of karst areas should be clarified, innovative technical means should be used to dynamically monitor the abandoned area of prime farmland and rocky desertified farmland, as well as their abandonment trend changes, the contribution of explicit abandonment in soil erosion control and ecological restoration of rocky desertification should be quantified, and the carbon sink impact of abandoned land should be comprehensively assessed. Therefore, it may offer suggestions for the rational allocation of social and ecological functions of farmland in karst areas.