To provide a high pressure type oxygen supply device and a chamber allowing a user to easily get into/out of the chamber.

The chamber 1 is split on a base 4 placed on a floor surface into a first split chamber 5 on the head side of a user and a second chamber 6 on the foot side of the user in the longitudinal direction. The first chamber 5 is slid on the base 4 in the longitudinal direction while being overlapped with the second chamber, and then opened/closed. The chamber 1 is formed in a truncated cone shape, and a bed 2 is provided in the chamber 1 with a reclining mechanism.