PURPOSE: To provide a means for securing a brake booster which is convenient for use and has a relatively simple form.

CONSTITUTION: A brake booster securing means includes at least one mounting bolt 4, a captive nut located on one side of a support opposite to that to which a booster is to be attached, and the support to which the booster can be attached being engaged by a bolt. The captive bolt is held against separation from the support and is also held against rotation by a retainer. A pilot section 25 on one end of the bolt locates within the captive nut so as thereby automatically position the nut to be cooperative with a threaded portion of the bolt. The bolt also serves to hold separable parts of the booster housing 1 against separation.