In this paper, we build a model based on the notion of green development that may be used to assess a three-dimensional ecological footprint. We design it by calculating two indicators, namely, footprint size and footprint depth. We perform quantitative research on ecological sustainable development. Based on our results, from 2010 to 2020, the per capita ecological footprint and ecological carrying capacity generally displayed a varying rising trend; the depth of the footprint has been maintained at 1.1364 gha/cap, and it is clear that the ecological footprint has constantly exceeded the ecological carrying capacity, which means that from 2010 to 2020, Gansu Province’s ecological and economic development was in deficit. Based on these findings, we offer sound recommendations for the ecological environment’s sustainable development in Gansu Province.