The objective of this development is to increase the earthquake resistance performance of gravity caisson quay wall by employing sheet pile at the foot of the caisson. Gravity caisson quay wall with sheet pile realizes the 0.05 point increase of seismic coefficient by comparing usual gravity caisson quay wall. This method can apply existing gravity caisson quay wall which is short of sliding resistance during earthquake. Quay wall structure becomes hybrid type by connecting the head of sheet pile and the caisson and shows both advantages of gravity type structure and sheet pile structure. Underwater shaking table test and 2D dynamic effective stress analysis were done for the proposed hybrid type quay wall structure. Gravity caisson quay wall was designed at the condition of 0.15 design seismic coefficient and 10m water depth at the foot of the structure. The result shows the necessity of 900mmdia. steel sheet pile for the condition of 0.2 design seismic coefficient. 50 percent reduction of caisson crest displacement during earthquake is also obtained. Design criteria for this hybrid quay wall structure is also proposed.