Provided is an arctic drill ship in which a weather tight structure protecting a drill floor and a drilling work area from outside air is coupled to a side strake around the drilling work area. It is possible to economically and easily manufacture the weather tight structure which minimizes the influence of outside air on the drilling operation in the polar regions, and it is possible to efficiently support the hull longitudinal strength and the weather tight structure with the use of the side strake structure solely. Therefore, a structure which may cause a disturbance in the drilling work area is minimized, and it is unnecessary to install a separate structural reinforcement part for a drilling workspace in the polar regions. In addition, the drilling workspace in the polar regions can be effectively ensured, and a spatial limitation in an upper portion of a moonpool can be solved.