With the developing of vehicle networking technology and artificial intelligence technology, intelligent connected vehicles are facing more and more serious cybersecurity threats and challenges. The privacy data in intelligent connected vehicles is becoming increasingly urgent. For privacy information protection problem of Android platform, we proposed a new transparent encryption scheme based on SM4 algorithm for intelligent connected vehicles. A transparent encryption method for Android platform is designed and implemented. The secret-key is generated by the Phone MAC address that fundamentally guarantees the security of user information. The system design adopts the MVP design pattern and completes the file transparent encryption system. Finely the system test results proven that the transparent encryption system can effectively encrypt and decrypt the specified files to protect the privacy data for Android smart terminal of intelligent connected vehicles.