With the rapid development of the global economy and internet technology, cloud computing technology has been advanced at a rapid pace. Cloud computing technology is a new development model for large-scale computing after distributed computing, parallel computing and grid computing. In the in-depth application of cloud computing services, cloud programs continue to expand. Due to the popularity of cloud computing services, cloud service security has become an important factor affecting its application and development. Cloud computing technology will be a public resource shared among computing resources, storage resources and others; it has also led to the lack of transparency and less control of IT assets, resulting in many business concerns about data loss and destruction. At present, the main risks to cloud computing lie in sharing, insecure interfaces, privileged user visits, identity counterfeiting, data security, management and legal affairs. To reduce or eliminate the main risks of cloud computing, encryption technology is adopted, with the introduction of strict identity authentication mechanism, strengthen management and safety supervision, as well as improvement on information security laws, regulations and other countermeasures.