Sample contamination is suppressed by strengthening the air barrier of a work opening portion. A safety cabinet includes: a work room; a front surface door covering a part of a front opening portion of the work room; and a work opening portion on a lower side of the front surface door allowing a worker to work with his or her hand in. An intake port suctions air in the work room and outside air through the work opening portion on a front surface side of a workbench in a lower portion of the work room. A straightening plate drawing an air flow and a linear light source are provided on the work room side of the front surface door and above a front portion of the work room.