Abstract: A sidearm mounting and locking apparatus comprises a base-plate adapted for surface mounting, the plate providing spaced apart guide-plates extending from the base-plate in side-by-side juxtaposition for cradling a sidearm therebetween. The guide-plates provide aligned pin apertures and a trigger blocking-pin adapted for engaging the pin apertures and positioned for disabling a trigger of the sidearm. A barrel supporting bracket assembly engages the base plate and is positioned for receiving a barrel of the sidearm in rest thereon. The barrel supporting bracket assembly includes a barrel-pin integral thereto and positioned within the sidearm barrel. The blocking pin is positioned for preventing withdrawal of the sidearm from the barrel-pin.