Abstract: In order to obtain new-typed cytoplasmic male sterile(CMS)line and male sterile mutant of rice, many methods, such as conventional breeding, induced breeding, tissue culture and in vitro induced mutation, are used to solve the problem of single source of cytoplasm in hybrid rice production, among which, in vitro screening shows conspicuous preponderance, though some questions still exist. It is no doubt that the male sterile frequency will increase considerably if male sterile mutants can be obtained directively through in vitro culture. In addition, factors affecting the in vitro screening of male sterile mutants are also discussed in this paper.