Abstract: A device and method are shown for testing a packer in a well bore where the packer has an internal bore for conducting fluids and external gripping and sealing means for gripping and sealing the surrounding well bore. The packer is first set at a desired depth within the well bore. The test tool is then made up on a tubing string and has an external collet for engaging a recess provided within the interior bore of the packer. An external shear sleeve on the test tool is initially positioned to underlie the collet fingers when the collet fingers are received within the packer recess to retain the packer on the test tool. A fluid port communicates the test tool internal bore with a pressure responsive area of the shear sleeve for shearing the sleeve and releasing the collet fingers. The packer is then tested by applying pressurized fluid to the well annulus above the set packer. By shearing off the shear sleeve, the test tool can be retrieved to the well surface, leaving the set packer in the well bore.