This is a renovation project of an industrial building. The original building was of brick, concrete and prefabricated panels structure located in 798 art area, Beijing. The design wishes to respect and maintain the features of the original building, while improving the functional layout of the modern art gallery, and upgrading the quality of the interior space. Based on the analysis of the original building, the focus of this renovation is to create changeful gallery visiting experience. Thus the following three designs are developed: 1. Making use of the crack of the heating pipes outside the building to build an intermediary space and thus creates a new image for the gallery. Using the rusted metal mesh panels to form a “入”shape structure which looks like a space floating outside the brick walls .One side of the space is folded as the main entrance and awning, and the other side is built as internal stairs of the building. Mirror glass curtain wall reflects the street views, changing the closed impression of the gallery and enlivening the contacts of internal and external vision. 2. New steel-structure parts were added to the gallery, which were connected by a glass bridge, in this way, an internal “three-dimensional triple house courtyard” was formed. The exhibition hall is a pure white box, which is different from the rough red brick exterior wall, and the natural texture of the precast slab was partly retained only on the roof. Visitors tour from the internal to the external and between upper floors and lower floors, experiencing the differences of transition from the old to the new and comparison between rough and smooth. 3. A “light well” was created for the original low space (clear height 2 meters ) through demolishing the floor and roof of the office area in the original building. Natural light gets through the 3rd and 2nd floor’s office area and reach directly to the gallery, which on the one hand reduces the sense of oppression results from the low floor height; and on the other hand broadens the visibility of different areas of the interior.