With the rapid development of network digital technology, the creation and dissemination of audio-visual works have changed greatly. Short video has appeared, becoming a new form of entertainment after words, pictures and music. The second creation of short video plays an important role in the short video industry, but under the current copyright law, the second creation of short video has caused a series of rights conflicts. Holding the "gold medal for exemption from death" of "reasonable use", the second creation of short videos has never stopped. Looking at the connotation and extension of "reasonable use", it is unrealistic to bring the second creation of short videos into the sphere of reasonable use, the dispute resolution process is fraught with difficulties. Based on the principles of fairness and efficiency, taking into account both the right of prior works and the enthusiasm of secondary creation, this paper suggests that in judicial practice, the "four-factor test" should be used to help judge whether reasonable use is constituted, new collective management organization of copyright and block chain intelligent contract should be constructed to solve the conflict of rights at the source.