Shikumen alleys are a combination of the traditional courtyard-style of Jiangnan folk houses and the adjacent form of European townhouses. They are a unique residential architectural style that combines Chinese and Western elements in Shanghai. They are mainly distributed in Luwan, Huangpu, Hongkou, Zhabei, Jing'an, Xuhui and other districts in the center of Shanghai, among which Luwan District has the largest number and the most complete types. Shikumen alleys were born in the Shanghai Concession in the mid-19th century. They were built by traditional Chinese craftsmen and were exclusively for Chinese people to live in. They were named "li". With the entry of foreign construction companies into the concession, the construction method changed. In 1880, the first batch of modern construction factories in Shanghai were born, marking the formation of Shikumen alley construction skills. In 1910, the French Concession in Luwan District promulgated the "Regulations on Highways, Buildings, etc.", which standardized the requirements for alley housing, formed a complete process from drawing design, construction registration, material prefabrication, decorative art to construction, and built a rich and diverse Shikumen alleys. After liberation, the Shikumen alley construction skills were transformed into maintenance and repair methods, which have been passed down to this day. Shikumen is called "Shihoomen" because its door frame is made of stone strips. In Shanghai dialect, "hooping" means wrapping something with another thing, so it is called "Shihoomen", which is later pronounced as "Shikumen". Shikumen lane construction has undergone a series of adjustments and innovations based on the characteristics of the times, regional characteristics and residential needs, evolving into improved lane forms such as Cantonese lanes, new lanes, garden lanes, and apartment lanes. Shikumen lane construction techniques grasp the humanized scale of space, widely adopt new technologies and processes for urban residential construction, and use overall procurement, batch construction, componentization and processization of technical processes, forming an economical and industrialized residential building construction method. The richness and innovative characteristics of this construction technique constitute a unique Shanghai-style architectural technique. As a new architectural style, it is a symbol of Shanghai people's pioneering a new life different from the traditional way and moving towards a new civilization. At the same time, it is very meaningful that it has created an unprecedented and special urban landscape for Shanghai. Since the 1940s, Shikumen lanes have basically stopped construction, and their construction techniques are only maintained in the repair and maintenance of houses. At the end of the last century, with the large-scale reconstruction and development of Shanghai, Shikumen lanes began to be demolished one after another. As for the remaining Shikumen lanes, due to long-term unreasonable use, modern living needs have also greatly conflicted with the original design functions of Shikumen residences, resulting in the existing Shikumen lane buildings facing the crisis of being completely demolished.