To provide a drainage method of a small well using together with a large depth vacuum drainage-a consolidation groundwater discharge method.

In the drainage method of the small well using together with the large depth vacuum drainage - a consolidation groundwater discharge method, after a boring (H2) of a narrow diameter having far smaller than a pipe hole (H1) for a super well point method has been applied to a position raising the water level of ground water sprung out to the surface of a ground (1) excavated by the super well point method, a riser pipe (5) equipped with a suction section (6) in the lower end is inserted and driven, the upper end site is connected to a header pipe (7) communicated with the inside of a pipe (3) for the super well point method, the ground water taking into the riser pipe (5) is supplied to the inside the pipe (3) for the super well point method by driving of the vacuum pump (14) and, at the same time, it is so constituted that the ground water can be exhausted to the outside from a lifting pump (10) for DW of the pipe.