Security and trustworthiness are extremely important requirements for cloud computing. How to protect critical application code and data on the cloud platform and prevent cloud service providers and other attackers from stealing user's confidential data is a difficult problem. In 2013, Intel proposed a new processor security technology SGX, which can provide a trusted execution environment for user space on the computing platform to ensure the confidentiality and integrity of critical user code and data. Since SGX technology is proposed, it has gradually become an important solution to cloud computing security issues. How to effectively apply SGX technology to protect application has become research a hotspot in recent years. In this paper, the mechanisms and SDK of SGX are introduced, and the bottlenecks such as security issues, performance bottlenecks, development difficulties, and function limitations faced by SGX application are summarized. The research progress of SGX application supporting techniques are analyzed and summarized, including SGX application security protection technique, SGX application performance optimization technique, SGX application assisted development technique, and SGX function extension technique. Finally, the development directions of SGX application supporting techniques are suggested.