Media,the medium of public opinion,is very important to correctly guide public opinion.Based on analyzing three typical cases on transgenic safety,this paper points out the problems relevant to legal system on public opinion guidance to the media and pertinently puts forward several suggestions on how to perfect the guidance of public opinion on legal system,such as perfection of relevant laws and regulations,implementation of legality of network public opinion,confirmance of legal status of network media,establishment of good faith system of media and improvement of legal awareness for media professionals.