In recent years,Non-Practicing Entities(NPEs)have been extensively engaged in patent litigation,which has brought great negative impact on industrial innovation and the patent system in the U.S..As NPEs have entered China to carry out patent layout and initiate litigation against Chinese enterprises,it is necessary to conduct in-depth research on NPE's response measures.This article analyzes the emergence of NPEs,their mode of operation,their impact on the U.S.,and regulation of NPEs in the U.S..It is found that NPEs have positive impact of revitalizing the patent trading market and reducing the cost of patent trade,while patent litigations by NPEs have brought negative impact on industrial innovation and patent system.In the U.S.,patent litigation of NPEs are mainly regulated by improving the patent examination system to control the quality of patent sources,and improving patent litigation rules to reduce their profit margins.Finally,based on the challenges posed by NPEs to China's patent system,countermeasures and suggestions were proposed from guiding NPEs to play a professional operational role,clarifying patent authorization standards,and improving litigation rules.