1949 After the liberation of Shanghai in May, the leaders of Longmen United Bookstore realized that the publication and distribution of scientific and technological books must have broad development prospects and hoped to make great achievements. In view of the large number of universities, industrial and mining enterprises in Northeast China, which have been liberated for a long time, there is a keen demand for scientific and technological books, so they sent people to Shenyang to set up branches in August 1949. Because the local Xinhua Bookstore, Sanlian Bookstore and some small bookstores don't sell science and technology books, Longmen Shenyang Branch has become an exclusive operation, retail and wholesale, and its business is booming. Especially on holidays, the store gives readers a 10% discount, which is even more busy. Shenyang branch has occupied almost the whole Longmen edition book market in Northeast China. After the founding of New China, Longmen sent people to Xi 'an and other places to open branches and expand the distribution business.

Since 1950, the branch libraries in Beijing and Hankou have expanded their turnover, which is convenient for libraries, scientific research units and readers to buy all kinds of scientific and technological books. In addition to selling Longmen edition books, they also distribute scientific and technological books published by other publishing houses, which are very popular with readers. According to statistics, the sales volume of foreign language books issued by Beijing Branch in one month is as high as 70% of the total sales volume.

1953 Longmen United Bookstore has strengthened its editing and proofreading power and improved its working environment in order to adapt to the substantial increase in the editing and publishing business of scientific and technological books.

After the founding of New China, Longmen absorbed a group of workers, distributed in various departments. In the past, the publications of Longmen United Bookstore were basically carried out through its own distribution network, and the publishing house met the readers directly, making it easy to exchange supply and demand information. After liberation, Longmen's publications were distributed by Xinhua Bookstore and China Book Publishing Company, and some of them were still sold by their own salesrooms. In order to further expand the distribution, 195 1 in August, Longmen United Bookstore organized China Science and Technology United Publishing House (hereinafter referred to as Kelian), a joint publishing organization with Yan Youzhi as its chairman, and joined 13 publishing units including China Science Book Instrument Company, Lixin Accounting Bookstore and Xinya Bookstore. Longmen and above outlets became outlets of Kelian, and agencies were set up in other cities for distribution.

During the "five evils" movement, the Association for Science and Technology was criticized by public opinion, and was considered to set up a distribution network in China to compete with the state-owned Xinhua Bookstore and China Book Distribution Company, and was dissolved after the movement. In addition to retaining retail outlets in Shanghai and Beijing, Longmen has also cancelled branches in various places and handed over the distribution business to Xinhua Bookstore.

Since 1950, Yan Youzhi has traveled back and forth between Beijing and Shanghai for many times in response to the Party's policy of using, restricting and reforming private industry and commerce. In publishing sci-tech books, Yan Youzhi was arranged by the General Administration of Publishing to establish contact with the Ministry of Higher Education, and accepted the task of compiling and publishing Soviet sci-tech textbooks issued by the Ministry of Higher Education, according to the original foundation of Longmen and the spirit of gradually becoming professional in business determined by the first China Publishing Conference. At that time, most editors of Longmen didn't understand Russian, so they made a surprise study. Because Longmen adopts the editing and proofreading system, these higher education textbooks will be divided into three classes according to their professional level: primary school (general process), middle school (key process) and junior college (registration process). Any proofreading must be carefully compared with the original text and strictly controlled. Due to the shortage of manpower, heavy tasks and insufficient funds, it often happens that a manuscript is divided into several wholesale banks, and several proofreaders go to the assembly line at the same time, and the work is quite tense. Longmen also undertakes the processing and ordering tasks of Chinese Academy of Sciences and Tsinghua University, and the total output has increased substantially year by year. Take the paper consumption of books over the years as an example: if the paper consumption of 1949 is 100, 1950 is 385,195/yes 1073,1973.

At the same time, the issuance of Longmen Books has also increased substantially year after year. The issuance amount of 100 and 1953 is 530037769 yuan, reaching 5728. With the increase of sales volume, the expenditure decreased, accounting for 27.24% of the issued amount in 1949, and decreased to 14.23% in 1953.