In the period of promoting urban sustainable development by stock renewal, orderly renewal of urban inefficient land to green infrastructure (GI) is an operational path to realize the reconstruction of ecological space and the optimization of ecological pattern in urban built-up area. In the existing researches, the evaluation of renewal priority of urban inefficient land mostly takes economic benefits as a basis of judging the development potential, and fails to consider the potential ecological benefits of the land parcels. Taking the downtown area of Guilin city as an example, this paper constructed a comprehensive index system to quantitatively evaluate the renewal potential of urban inefficient land from the perspective of economic and social benefits by using analytic hierarchy process, entropy weight method and TOPSIS method. Then, using the Least-Cost Path and the Circuit Theory method, we adopted the normalized least cost corridor value and the centrality value to evaluate the relative importance of urban inefficient land for the improvement of landscape connectivity in the study area. Finally, using two-dimensional discriminant matrix method, the priority of urban inefficient land renewal to GI was evaluated by integrating the results of renewal potential evaluation and importance analysis. The results showed that:(1) the area of inefficient land parcels with high renewal potential accounted for 38%, which were relatively concentrated in the west and north of the study area. (2) The renewal of inefficient land to GI could significantly improve the overall landscape connectivity of the study area, and for these inefficient land parcels, there were significant differences in their potential of serving as corridors and stepping stones after renewal. The area of inefficient land parcels which were highly important for improving landscape connectivity accounted for 40%, and they were mainly distributed in the north, west and south of the study area. (3) There were obvious differences between the results of inefficient land renewal potential evaluation and the results of importance analysis based on the improvement of landscape connectivity in some regions. The area of inefficient land parcels with high priority for renewal accounted for 21%, and they were mainly distributed in the north and southwest of the study area. For these inefficient land parcels, different renewal planning measures should be taken according to their different renewal priority grades. The research results can provide a new method framework and decision-making reference for the planning practice of urban inefficient land redevelopment and the optimization of green infrastructure network patterns.