[Objective] As a key economic zone in central China and an industrial base dominated by energy and heavy chemicals, Taiyuan City, Shanxi Province aims to achieve high-quality growth by deeply understanding the relationship between urban transformation and ecological-environmental quality as well as the characteristics of land-use transition and its impact on habitat quality. This understanding provides a basis for and support for urban land use transitions. [Methods] The geoscience information map, drive-pressure-state-influence-response (DPSIR) framework, and InVEST model were employed to explore the characteristics of land-use transition as well as the spatiotemporal changes in ecological security and habitat quality in Taiyuan City from 2011 to 2021, and their impacts on habitat quality resulting from land-use transition. [Results] ① During the study period, the main manifestation of land-use transition in Taiyuan was the mutual conversion among land for cultivation, forests, construction, and grasslands. Grasslands had the largest outflow area, whereas land for forest and construction had the largest inflow areas. ② Taiyuan City’s ecological security index showed an upward trend, rising from 0.266 1 in 2011 to 0.725 5 in 2021. However, habitat quality exhibited a slow downward trend, declining from 0.576 8 in 2011 to 0.573 5 in 2021. ③ The index for ecological-environmental quality revealed a slight downward trend from 2011 to 2021 but remained fairly stable overall. Conversion from cultivated land to grasslands contributed the most to habitat quality, with a contribution rate of 3.354%. The primary reason for the decline in habitat quality was the conversion of land meant for cultivation to land meant for construction, with a contribution rate of 8.838%. [Conclusion] The characteristics of land-use transformation in Taiyuan City are clear. Changes in land use have degraded the ecological environment, and there are differences in ecological security and habitat quality. The mutual conversion between land for cultivation, forests, construction, and grasslands is the main factor affecting the quality of the ecological environment.