Adult age-group differences in environmental judgment may be expressed through domain-specific differences in comparative appraisal under standardized exposure conditions. Drawing on environmental appraisal theory, this study examined whether perceived environmental support is organized as a domain-specific comparative appraisal process and whether age group moderates the distribution of such appraisal across domains under standardized exposure conditions. Using a within-subject comparative rating design, 804 adults from South Korea and China evaluated two thematically matched cultural exhibition settings presented through standardized visual materials. Perceived environmental support was assessed using 17 study-specific appraisal items aggregated into five theory-guided domains for domain-level comparative analysis. Results from the full-sample analysis showed significant Context × Domain and Context × Domain × Age Group interactions in linear mixed-effects models, indicating that comparative judgments followed a domain-differentiated pattern and that this domain profile varied across age groups rather than reflecting a uniform preference for one context. The overall domain-differentiated pattern was highly stable under repeated age-balanced subsampling, whereas the age-moderation effect showed lower resampling stability. Age-group profiles showed no simple monotonic progression across adulthood. Together, these findings support a domain-distributed account of environmental appraisal in which age-group variation is located in the configuration of support-relevant appraisal rather than overall evaluative tendency.