To provide a spin treatment device and a wet-type treatment device capable of conducting the spin treatment or the wet-type treatment by keeping high quality state of a wafer, securing a high-level of safety, and suppressing a foreign body stuck to the wafer.

A spin treatment device comprises a spin cup 1 freely opened above, a windshield cover 4 on the spin cup 1, an in-cup rotating table 2 in the spin cup 1, and an intake 8 and an opening section 9 for an arm provided to the windshield cover 4. The device is structured so that a displacement Eout of an evacuated gas from the spin cup 1 through an exhausting line 7b equal to the intake (A1+A2) or more of the intake gas from the intake 8 and the opening section 9 for the arm. An air current guide section causing directing an air current caused by the rotation of a wafer 5 into the windshield cover 4 at the opening end of the opening section 9 for the arm of the windshield cover 4.