In the context of rapid globalization and the swift advancement of information technology, satellite internet has emerged as a critical infrastructure for global communication services, drawing unprecedented attention to its security challenges. Traditional security measures are increasingly inadequate, struggling to meet the high standards of security, transparency, and reliability required by modern communication networks. Blockchain technology, with its unique attributes such as decentralization, immutability, and smart contracts, presents a promising solution to these security concerns. This paper explores blockchain-based intrinsic security mechanisms for satellite internet, with a particular emphasis on key components such as trusted accounts, data encryption, and access control. The objective is to propose a robust set of strategies and provide technical support for the security management of satellite internet, ultimately aiming to enhance the security and reliability of satellite communication networks on a global scale.