The evolution of Web 3.0 has brought decentralized governance to the forefront, with Delegated Proof-of-Stake (DPoS) mechanisms playing a pivotal role. However, bribery and collusion pose significant risks to the integrity of DPoS systems, undermining the decentralization that is fundamental to Web 3.0’s vision. This paper presents TriGuard, an enhanced governance mechanism designed to curb bribery and promote fair participation within DPoS frameworks. TriGuard integrates a tripartite evolutionary game model with incentive mechanisms tailored for voting participation, bribery reporting, and supervisory actions. Through extensive simulations and theoretical analysis, we demonstrate that TriGuard effectively increases voter engagement, strengthens supervisory oversight, and diminishes the influence of malicious actors. The proposed mechanism reduces centralization risks and enhances security, creating a more decentralized governance framework for Web 3.0 ecosystems.