This study explores the characteristics of and changes in Korean landscape architects’ attitudes toward ecological design strategies and theories over the last three decades. Methodologically, this study includes a literature review and incorporates data from case studies and site visits. It discusses Seoul-specific contexts regarding environmental conditions, urban morphology, administrative agency, and design theory and practice. It redefines ecological parks, expanding their scope using physical and non-physical ecological processes. Considering this redefinition, this study categorizes the five main attitudes of contemporary Korean landscape architects towards ecological design: providing wildlife habitat, constructing aesthetic experiences, the phasing strategy, developing environmental learning programs, and designers’ metaphoric expression. Through these attitudes, this study chronologically explores gradual and constant changes in design strategies and the discourse on ecological design. Specifically, in the 1990s, landscape architects emphasized the representation of ecosystems by constructing wildlife habitats. In the early 2000s, ecological parks were artistically designed as urban parks by reusing post-industrial landscapes. Around the 2010s, landscape architects developed resilient and adaptive design strategies to flexibly respond to uncertain changes in natural and urban ecological circumstances. Since the 2010s, landscape architects have continually expanded the scope of ecology to cover physical, non-physical, urban, and social infrastructures, including public transportation, as well as political, social, and cultural structures and virtual and augmented landscapes. This study can contribute to the field literature while adding a valuable overview of the understudied Korean context.