Abstract: Investigating the spatio-temporal evolution characteristics and coupling relationships of the "Production-Living-Ecological" (PLE) spaces in Neijiang City not only reveals the spatio-temporal evolution patterns of these spaces but also provides a scientific basis for formulating regional territorial spatial planning schemes. Using townships in Neijiang City as research units, this study constructed a PLE spatial zoning table based on land use type data from 1990 to 2020, and employed spatial auto-correlation and a coupling coordination degree model to explore the spatio-temporal evolution characteristics and coupling coordination relationships of the PLE spaces in each township. The research findings indicate that: (1) From 1990 to 2020, the area of production space in Neijiang City exhibited minor fluctuations. The living space area expanded, primarily along major transportation routes and core urban clusters. The expansion of living space encroached upon ecological space, leading to a reduction in the ecological space area. (2) Over the 30-year period, all three spatial types showed clustered distribution patterns. Production space was concentrated in areas with favorable natural conditions and convenient transportation; living space was clustered in township centers and urban cores; ecological space was primarily distributed in mountainous regions with higher elevations. (3) During the study period, the coupling degree of PLE spatial functions increased, but the coupling coordination degree decreased. This indicates that the encroachment of living space upon ecological space has exceeded the threshold for synergistic optimization between production and ecological spaces. It is recommended to strengthen the optimization of layouts in urban fringes and ecologically sensitive areas to enhance coordination levels. The results provide theoretical guidance and a scientific basis for the coordinated development of PLE spaces, the development and optimization of territorial spatial patterns, coordinated urban-rural development, and ecological security construction in the townships of Neijiang City.