In the context of global warming, the 2015/2016 extreme El Nino event received much attention. This event was a mixture of central Pacific (CP) and eastern Pacific El Nino. Our study shows that both the westerly wind bursts and the North Pacific Meridional Mode contributed to the generation of this event. By comparing the 1997/1998 event, the 2015/2016 event and the CP event, the 2015/2016 event occurred in the warm background and shared similar development pattern with the CP event. Whats more, the rapid decline of sea surface temperature anomaly in the 2015/2016 event was related to the continued easterly anomalies and the weakened zonal current advection in the eastern equatorial Pacific. Compared with the 1997/1998 event, the ocean dynamic adjustment of the 2015/2016 event was weak, which was mainly reflected by weaker thermocline feedback and its associated fluctuations near the equator. Moreover, the zonal advection feedback was more efficient than the thermocline feedback, and the atmospheric forcing and its anomalous values in the central equatorial Pacific were larger. In addition, during the 2015/2016 event, the changes of the upper-ocean heat content in the equatorial region and the nearequatorial region were basically negatively correlated, and the changes were relatively synchronous. In the decay phase, the loss of ocean heat content mainly occurred in the 5°S-5°N region with significant heat transport to the higher latitudes.