Abstract:The number of patent applications in China has increased year by year, and there are also a lot of abnormal patent applications at the same time. The policy has been increasing to the impact of abnormal patent application, but there is no objective measures to identify abnormal patent applications. This paper gives the characteristics of abnormal patent applications, and designs a patent retrieval mode for retrieval and verification. The results show that the abnormal patent applications have the characteristics of applying for lots of patents in a short time, using cost reduction policy, giving up entering into the substantive examination phase, low quality of patent documents,and attempt to get subsidy.Therefore, some suggestions are given to restrain abnormal applications, including establishing objective measures to identify abnormal patent applications for the examination department, the establishment of abnormal application blacklist, adjustment of reduction policy, etc.