Smart contract technology， as a milestone of blockchain 2.0， has received widespread attention from both academic and industry circles. It runs on an underlying infrastructure without trusted computing environment and has characteristics that distinguish it from traditional programs， and there are many vulnerabilities with huge influence in its own security， so that the research on security auditing for it has become a popular and urgent key scientific problem in the field of blockchain security. Aiming at the detection and automatic repair of smart contract vulnerabilities， firstly， main types and classifications of smart contract vulnerabilities were introduced. Secondly， three most important methods of smart contract vulnerability detection in the past five years were reviewed， and representative and innovative research techniques of each method were introduced. Thirdly， smart contract upgrade schemes and cutting-edge automatic repair technologies were introduced in detail. Finally， challenges and future work of smart contract vulnerability detection and automatic repair technologies for online， real-time， multi-platform， automatic， and intelligent requirements were analyzed and prospected as a framework of technical solutions.