Abstract��By the introduction and breeding test of new Undaria pinnatifida variety in 2010, the appropriate environmental conditions and breeding technologies of farming Undaria pinnatifida in southern China has been explored. Technologies such as key points of daily management and optimum water layer of breeding Undaria pinnatifida had been summed up for farming in Guanwu Sea area, Fujian province, Lianjiang County, Xiaocheng townships. The problem of had seedlings cropped by Siganus fuscescens had also been resolved. By compare the outcome of Undaria pinnatifida and sea tangle breeding, the conclusion had been drawn that Undaria pinnatifida breeding surpasses sea tangle as long as the benefit is concerned. All these build a solid foundation for the extension of Undaria pinnatifida breeding in Fujian province or in southern China.