The ocean surface and subsurface biophysical responses and their feedbacks to super typhoon Nida (2009) are investigated. Nida experienced two Category 5 stages: a rapid intensification stage that was fast moving along a straight-line track, and a rapid weakening stage that was slow moving along a sharp-left sudden-turning track. In the first Category 5 stage, Nida caused an average sea surface temperature (SST) cooling of −1.44 ℃, a sea surface height anomalies (SSHAs) decrease of −5.00 cm and a chlorophyll-a (chl-a) concentration increase of 0.03 mg m−3. During the second Category 5 stage, Nida induced a strong cold cyclonic eddy (SSHA < −60 cm) by strong upwelling due to the slow speed of the sudden-turning track, which caused the maximum SST cooling of 6.68 ℃, a sea surface salinity increase of 0.6 psu, a long-lasting chl-a bloom that exceeded 0.6 mg m−3 and the Kuroshio Current strengthening of 0.25 Sv, resulting in substantial impacts on the ocean ecological environment. Furthermore, the enhanced ocean cold wake and the longer air-sea interaction in turn decreased the average inner-core SST of −4 {degree sign}C and the corresponding enthalpy flux of −780 W m−2, which induced a notable negative feedback to the typhoon intensity by weakening it from Category 5 to Category 2. Our findings provide positive evidence that enhanced oceanic environmental responses and feedbacks can occur under sudden-turning and/or lingering tracks, providing insight to ocean-typhoon interactions.