On the issue of art copyright infringement, currently only law professionals have conducted research and discussion, but most of the studies focused on the practice of legal principles and the applicability and change of theories, little efforts were spent on the comparison and contrast between the copyright law and the creator's design process from the artist's perspective. The purpose of this study is to analyze the existing art copyright violation cases, and in a colloquial way briefly describes the legal definition of an illegal reproduction of art works, and the elements for a legal judgment. Then an insight is obtained from the cases and a conclusion is drawn on the details ignored by designers or not recorded in the creation process, and a set of corresponding codes against plagiarism is proposed. It is expected that due to the conclusion of this study, designers can pay attention to and record the decision points for key designs, and avoid unnecessary disputes. A concept of avoiding copyright infringement based on the study is proposed accordingly.