Mindfulness is a psychological construct that enhances sustainable behaviors, environmental behavior, environmental consumption, mindful consumption, and water and energy sustainable consumption. The state of mindfulness can be affected by the determinator of the physical environment as architecture via the architectural atmosphere. The previous studies show that the discrete areas of knowledge between architecture and mindfulness are still widely unknown. However, image-centered social media platforms such as Instagram seem to be able to provide big data for studying people’s perceptions of architecture. Thus, this study aims to describe the concept design and characteristics of architectural atmosphere in architecture images tagged mindfulness posted to Instagram. A coding framework developed from a previous systematic literature review was conducted for this content analysis. A total of 354 architectural images were screened, coded, and analyzed by five architects. The results highlight that the Japanese traditional architecture (59.20%) looks to be the most architectural atmosphere concept that influences mindfulness, following by Biophilic Design (33.05%), and Buddhist contemplative space (20.06%). In addition, it was found that the most common architectural atmosphere characteristic fostering mindfulness performed calm space (73.58%), focus object (54.45%), concrete material (85.71%), hue color (78.17%), hard light and shadow (78.98%), and view with a tree (60.11%).