The theme of the Mitsubishi Group pavilion for Expo 2025 Osaka, Kansai—“keeping the world vibrant”—is reflected in the core design concept of life, nature, and human society as interconnected and interactive elements. The pavilion consists of a belowground level and two aboveground levels with layered geometries, starting with a semi-underground elliptical space. Overlapping this space is a rhombus whose vertices touch the interior curve of the oval. A rectangle, laid out within the rhombus, provides an additional structural layer. Each of these three geometric forms symbolizes a different element—the ellipse represents life, the rhombus represents nature, and the rectangle represents society—while the architecture expresses their mutually supportive relationship.
The pavilion has no single front-facing façade; instead, the all-directional design is intended to be visually engaging from both the main plaza on the east gate side and the peripheral roads on the opposite side.
The interior space is designed to allow visitors to explore the “body” of the pavilion three-dimensionally, engaging in various experiences throughout areas centered around the main video exhibition. Upon arrival, visitors descend into the semi-underground space known as the Waiting Park. The design blocks direct sunlight and facilitates cool air flow, creating a shaded and comfortable waiting area for all visitors. From there, visitors proceed to the Pre-Show on the first level to view an orientation video before moving on to the Main Show on the second level. After an immersive video experience, visitors return to the first floor and pass through the Post-Show area before reaching Sankaku Park (lit. Triangle Park) at the structure’s tip, which feels as if it is suspended in midair.
A key concept that inspired the pavilion’s design was the circular use of resources on a small scale. The pavilion will be dismantled after the six-month duration of the Expo, and the site will be restored to its original state. The design minimizes direct contact between the building and the ground, ensuring that the soil—a precious resource—is restored with minimal environmental impact. The excavated soil will be repurposed for site reclamation, reinforcing the commitment to circular use.
For the finishes, the design team explored alternative uses for temporary construction materials, reimagining them as primary finishing materials. By considering how these materials could be repurposed after the Expo, the design aims to reduce both economic and environmental impact. The pavilion’s exterior features an equal combination of polycarbonate panels and steel construction scaffolding. Sandbags, steel pipes (single-tube scaffolding), tread plates, lighting fixtures, fans, and other materials used in the pavilion can all be repurposed on-site. Additionally, practical materials such as blue tarps, ceiling framing materials, laminated timber, oriented strand board (OSB), and chain mesh fencing are cleverly integrated into the finishes and interior design.
Air-conditioned areas were minimized, with most of the interior designed as a semi-outdoor space reminiscent of the engawa (veranda) in traditional Japanese houses, reducing the cooling load. The design also avoids complex or theatrical lighting; instead, soft illumination from within the building spills outward, creating a gradient of light and shadow. This gentle, nuanced lighting honors the Japanese cultural concept of darkness while imbuing the space with depth and richness.
The Mitsubishi Pavilion for Expo 2025 Osaka, Kansai is designed and supervised by Mitsubishi Jisho Design. It is located on Yumeshima Island in Osaka City, Osaka Prefecture, Japan. The pavilion occupies a site area of 3,476.46 m², with a building area of 1,241.88 m² and a total floor area of 2,075.83 m². The structure consists of two stories above ground and one basement level, with a maximum height of 16.50 meters. The pavilion is committed to sustainability, with every aspect—from minimizing energy consumption to repurposing materials—designed to create a small-scale circular architecture from construction to demolition.
Photographer: Nacasa & Partners Inc.
