Abstract: Major water diversion projects usually exhibit linear distribution, with multiple contractor teams executing parallel construction during implementation.To address the opportunistic behaviors of multiple parallel contractors in such projects, an evolutionary game model incorporating psychological tendencies was developed, involving the project owner and multiple contractors.Using evolutionary game theory, the dynamic evolution processes and strategy selections of multi-party stakeholders were examined.The results indicate that the tripartite dynamic game among the owner, Contractor 1, and Contractor 2 does not uniformly converge to a single stable strategy set.Instead, varying behavioral orientations within distinct probability ranges lead to different payoff outcomes.The contractors′ behavioral choices are primarily influenced by three factors: the magnitude of material rewards in tournament incentives, the utility of fairness preferences, and the speculative gains from opportunistic behaviors.The key to achieving the system′s optimal game equilibrium lies in ensuring that the benefits of "effortful" behaviors outweigh those of "opportunistic" behaviors for contractors.Thus, designing tournament incentive schemes based on these critical factors is particularly important.