Abstract. Reliable CNC machine tools can make the industrial production efficient and stable. The reliability of CNC system is a hot topic in the field of mechanical engineering. It is very meaningful to make suggestions to improve the reliability of CNC machine tools by collecting and analyzing the operation data of CNC machine tools. The data cloud platform of CNC system is designed and implemented in this paper. It is used to collect the data of CNC system and provide data service to the public. This data cloud platform, based on server cluster and big data processing framework, can effectively receive, forward, store and publish data of CNC system. The experiment proved that the system has high availability, high concurrency, high throughput and reliable disaster recovery ability.