With the promotion of rapid economic and social development, land use has undergone profound processes of transition worldwide, leaving the production–living–ecological spaces (PLES) and landscape pattern reconfigured, thus further affecting regional eco-environmental quality and landscape ecological risk. This paper first introduces a research framework of comprehensive eco-environmental effects caused by shifts in land use, to analyze the relations and interactions among land use transition, interconversion of PLES, eco-environmental quality, and landscape ecological risk, and then this framework was applied to the empirical analysis of the Guangxi Zhuang Autonomous Region (Guangxi), to examine the comprehensive eco-environmental effects caused by land use transition there. The results show the following: (1) During 1990–2018, ecological space in Guangxi tended to continuously shrink in area, while the area of production and living space kept expanding. The areas of forest ecological land, grass ecological land, and agricultural production land clearly decreased over time, having been mainly converted into both urban living land as well as industrial and mining production land. (2) The eco-environmental quality in Guangxi showed a trend of continual decline, this characterized by high and medium-high quality zones decreasing in area as the low-quality zone expanded. Further, the spatial distribution of eco-environmental quality tended to diminish when moving from Guangxi’s surrounding towards its central and southern parts. (3) However, the landscape ecological risk continued to rise mainly because of reductions in ecological space. Its spatial distribution was the inverse of that of eco-environmental quality; i.e., being at high risk in the central and southern parts, but lower in the surroundings. (4) The bivariate global Moran’s I analysis revealed a significant negative correlation between the eco-environmental quality and landscape ecological risk. Going from remote mountainous and hilly areas to rural areas, and then into urban areas, the eco-environmental quality displayed a gradually decreasing trend, while landscape ecological risk was initially reduced but then augmented. We conclude that land use transition in Guangxi has caused a continuous reduction in its regional eco-environmental quality, and also exacerbated its landscape ecological risk. Hence, it is of great importance to balance the PLES and optimize the landscape pattern, so as to restore the eco-environmental quality while also mitigating the landscape ecological risk of Guangxi and similar regions.