In 1950,Saccharina japonicahad been successfully transplanted in Qingdao. This success laid the foundation for the farmingS. japonica. During 1953-1955, the relationship between the gradient of sea area and the growth ofS. japonicawas explored, affirming that nutrient played a decisive role for the growth ofS. japonica, and providing a basic solution for the cultivation ofS. japonicain the nutrition-deficient sea area in the north coast of China. During 1956-1957, southward extension of commercial cultivation ofS. japonicafrom Qingdao to Shengsi was successful. The relationship between sea state conditions of the south coast of China and commercial cultivation ofS. japonicawas explore, and thus the groundwork was laid for a large-scale southward extension of its cultivation industry. In 1957-1958, temperature fitness of growth and development of sporophyte, and cultured conditions with natural light for seeding rearing ofS. japonicawere investigated, and thus a new method of seedling ofS. japonicais put forward, ensuring the demand of seedling ofS. japonicain the commercial cultivation. In 1959, genetic regularity of economic characters ofS. japonicawas investigated. A new high-yielding strain named “59-1” with high-temperature-tolerance and good economic characters was bred successfully. Moreover, the relationships between growth and development ofS. japonicaand temperature, light, and nutrient were explored. A comprehensive system for science & technology of cultivation ofS. japonicahad been set up, raising the level of scientific research ofS. japonicain China to the world's advanced level.