To provide a safety cabinet which enables the fixing of both elbows without bringing the arms into contact with the front suction opening of a working bench being a contaminated area.

Providing an arm support to hold the operator's arm outside a work area independent of the working bench enables the fixing of both elbows without bringing the arm into contact with the front suction opening of the working bench being the contaminated area, and improvement in experimental operability and maintenance of safety. In the safety cabinet, a rod-shaped arm support is arranged at a front lower part in order to hold the operator's arm outside a workspace.