The invention relates to a rock-socketed single 
pile foundation through 
offshore wind power and a construction method of the rock-socketed single 
pile foundation. The rock-socketed single 
pile foundation comprises a steel 
pipe single pile which is positioned in the center, wherein the lower end of the steel 
pipe single pile is inserted into a 
seabed, and the upper end of the steel 
pipe single pile is positioned above the 
sea level; a fan 
tower cylinder is mounted at the upper end of the steel pipe single pile, and a plurality of steel pipe grouting piles which are fixedly connected to the steel pipe single pile are arranged at intervals at the internal circumambient part or the periphery in the steel pipe single pile; the lower ends of the steel pipe grouting piles are inserted into the 
seabed, and the upper ends of the steel pipe grouting piles are positioned above the 
sea level; the inner parts of the lower ends of the steel pipe grouting piles are grouted with concrete socketed piles of which the lower ends penetrate through the lower ends of the steel pipe grouting piles to be embedded and fixed in a baserock layer of the 
seabed. According to the rock-socketed single pile foundation disclosed by the invention, the difficult problem that at current, in China, full 
cut-off sock-socketed construction of large 
diameter pile foundation cannot be realized is effectively solved, and besides, the horizontal 
load bearing capacity and the antidumping capacity of the pile foundation are improved; the dynamic response of infrastructures is reduced, the application scope of the single pile foundation is enlarged, and the single pile foundation disclosed by the invention has a high application value.