Handgun locking apparatus for securing a handgun in a holster includes a lever member including a body having a forward and rear end portion mounted to the holster and a spring element projecting forwardly and outwardly from the front end portion of the body for contacting an interior surface of a holster for biasing the body against a handgun. A locking flange on the forward end contacts a handgun to positively engage a portion of a handgun to inhibit withdrawal of a holstered handgun. An operating arm extends rearwardly from the rear end portion of the body for moving the body away to move the locking flange away from a handgun. A positioning member is affixed inside a holster for engaging a handgun inserted in a holster to position a portion of a handgun in contact with the locking flange. A tension device is mounted to the inside of the holster for positioning the gun properly with respect to the locking apparatus.