Recent studies have shown a significant deterioration in the mechanical properties of reinforced concrete structures exposed to prolonged seawater-induced chloride corrosion. This article focuses on investigating the oblique collision responses of corroded bridges. This study analyzed the responses of bridge piers in vessel velocity changes during vessel-bridge collisions at different oblique impact angles (15° and 30°). Furthermore, surrogate models were developed to predict the response of corroded bridge piers under vessel collisions, and it is found that the response surface methodology models can provide good accuracy. By using this surrogate model, the study conducted a parameter analysis on the remaining bearing capacity of the bridge piers and performed vulnerability assessments under oblique vessel collisions, obtaining vulnerability curves for different collision scenarios.