The port-hinterland system, encompassing seaports and dry ports, has evolved into the backbone of international trade. Due to their unique geographic locations and critical socioeconomic functions, ports are particularly susceptible to a range of risks. Port authorities (PAs) can address these challenges through targeted preventive efforts, which aims to reduce the probability of risk occurrence, and adaptive efforts, which seeks to mitigate potential damage. However, intermodal interactions and the asymmetric risk behaviors exhibited by ports under risk probability ambiguity present significant challenges for PAs making risk-responsive investments. This study develops a two-stage game model to examine the effects of asymmetric risk behavior and risk probability ambiguity on strategic investment decisions. Our analysis reveals that prevention are susceptible to free-rider effects, which are further exacerbated by risk behaviors and mitigated by investment strategy differentiation. Moreover, we demonstrate that, as a general guideline, seaport authorities should prioritize adaptation, while dry port authorities should focus on prevention, with adaptation being the primary strategy when the level of risk aversion is low. These findings provide valuable managerial insights for improving the risk management and resilience of the port-hinterland system.