At the end of the reign of Qing Daoguang, Dong Haichuan, the founder of the Bagua Quan system, taught his art to many closed-door students in Beijing. One of those students was Yin Fu, who inherited all of Dong's teachings on Bagua Quan. When Yin Fu taught students, he also completely transmitted Master Dong's style. Because people are different and because their abilities are many, therefore the students that became famous are also many, such as Ma Gui, Yang Junfeng, He Jinkui, Yin Yuzhang, Li Yongqing, Jin Liuhui, Cao Zhongsheng, Men Baozhen, Gong Baotian, etc. Later people commemorate the tremendous contributions that Grandmaster Yin Fu made to the art of Bagua Quan by calling his Bagua Quan "Yin Branch Bagua Quan." And when Master Gong Baotian inherited this art, people called it "Yin Style Gong Branch Bagua Quan." Afterwards, when Gong Baotian's "top student", Sun Ruwen, inherited this martial art, he called it "Qianzi Men". Its full name is "Yin Style Gong Branch Qian Gua Bagua Quan (Inner Eight Trigrams – Qian Character School)." The author studied with Sun Ruwen for thirty years from June 1953 through February 1984 and deeply got these transmissions. He underwent innumerable hardships, progressing deeper into the art and doing investigative research. Finally we have a clear picture of the development and history of Yin Style Gong Branch Bagua Quan.