In this study, the impact of oceanic processes on the sensitivity of transient climate change is investigated usingtwo sets of coupled experiments with and without tidal forcing, which are termed Exp_Tide and Exp_Control, respectively. After introducing tidal forcing, the transient climate response (TCR) decreases from 2.32 K to 1.90 K, and the surface air temperature warming at high latitudes decreases by 29％. Large ocean heat uptake efficiency and heat storage can explain the low TCR in Exp_Tide. Approximately 21％ more heat is stored in the ocean in Exp_Tide (1.10×1024J) than in Exp_Control (0.91×1024J). Most of the large ocean warming occurs in the upper 1000 m between 60°S and 60°N, primarily in the Atlantic and South Oceans. This ocean warming is closely related to the Atlantic Meridional Overting Circulation (AMOC). The initial transport at mid- and high latitudes and the decline in the AMOC observed in Exp_Tide are both larger than those observed in Exp_Control. The spatial structures of AMOC are also different with and without tidal forcing in present experiments. The AMOC in Exp_Tide has a large northward extension. We also investigated the relationship between AMOC and TCR suggested by previous studies using the present experiments.