To provide a pressure resistant container of a water filtration device which is simple in disassembly and assembly when exchanging materials for filtration and is highly durable under repetitive use by adopting members consisting of specific shapes and decreasing the number of component members.

A cylindrical body having an annular engaging edge to be engaged along the top surface peripheral edge of a cap body fitting to a container body and a threaded part corresponding to the threaded part of the container body is used as a connecting member when connecting the container body and the cap body via an annular gasket. The structure which fits the same to the cap body and is screwable to the container body is adopted.