[Purpose] We aim to examine the factors that may affect the patent examination cycle and explore the mechanism behind the patent examination cycle in the field of artificial intelligence in China. [Method] This article takes 78,254 invention patent applications in the field of artificial intelligence in China as the research object, uses the Kaplan-Meier method in survival analysis and the COX proportional hazard regression model to explore the overview of patent examination in the field, and analyzes the characteristics of patent objects and patent subjects based on characteristics, explore the factors that significantly affect the patent examination cycle in this field. [Results] The results show that the average survival period of the overall Chinese invention patent examination process in the field of AI is 32.81 months. Among them, the number of claims, the number of IPC classification numbers, and the number of inventors is the protective factors of the patent examination cycle, which promotes its extension; the number of patent citations is a risk factor, and the more patent citations, the shorter the time required to obtain authorization. Among the types of applicants, universities and scientific research institutions, as well as institutions and organizations, all spend a shorter time on patent examination than individuals. Surprisingly, companies will reduce the risk rate of patent application-authorization, which requires a longer patent examination cycle. [Limitations] The patent examination cycle is closely related to the examination process of the patent office and the personal characteristics of patent examiners. The article failed to obtain more fine-grained data related to it for analysis. [Conclusion] In order to optimize the patent examination procedure and shorten the patent granting cycle, this paper proposes that we can further combine different technical fields and the characteristics of the applicant to establish a diversified examination mode, strengthen the use of automated technology in the patent examination process, and establish classification examination standards to improve the overall patent examination efficiency.