Provided is a decompression device that varies a stimulus and tightening force to a penis by adjusting pressure in a container. The decompression device is mounted to the ejaculation promotion device and includes an ejaculation promotion apparatus and a container, which is configured to decompress the container, the ejaculation promotion apparatus includes an insertion empty space and a valve section that enables communication between an inside and an outside of the insertion empty space, the container accommodating the ejaculation promotion apparatus, and the decompression device includes: a negative pressure introducing section that communicates with an air vent hole provided in the container； a negative pressure generating section that generates a negative pressure to be introduced into the container through the negative pressure introducing section and the air vent hole； and a negative pressure adjusting section that adjusts the negative pressure supplied to the container through the negative pressure introducing section.
