Collection 004 is an album by the Japanese noise musician Merzbow. It is the fourth volume of the Collection series. The first five volumes were recorded for Ylem and consist of studio sessions with Kiyoshi Mizutani, then a member of Merzbow. However, Ylem went out of business before they could be released. Masami Akita then released them himself and recorded five more at home using previous Collection session recordings mixed with new material and effects.