With the continuous expansion of cyberspace boundaries, trust-related security incidents are increasing annually, posing severe challenges to the cyberspace trust system. However, current research mostly focuses on macro-policy analysis and the application exploration of specific trust models, with insufficient systematic exploration of the developmental requirements and characteristic elements of trustworthiness. To address this gap, this study reviews the policy evolution trajectories of cyberspace trust frameworks across nations, analyzing the developmental demand for trust system models. Subsequently, we propose a model framework for the cyberspace trust system from a technical perspective, grounded in the cyberspace technological architecture comprising the communication, network, system, and application layers. Through a layer-by-layer analysis of trust challenges and corresponding mitigation techniques, the study further identifies five core functional characteristics essential for cyberspace trust: identity authentication, authorization management, accountability, data trustworthiness, and supply chain and service trustworthiness. To validate the model's applicability, we conduct an in-depth analysis of trust risks and key technical countermeasures across four representative scenarios: extreme-condition cyberspace, artificial intelligence, data flows, and the Internet of Vehicles. Furthermore, recommendations are proposed to support the development of China's trustworthy cyberspace ecosystem, providing theoretical foundations for policy formulation and technical architecture design.