Abstract: An apparatus for calibrating an archery bow is described. The apparatus provides for securing a bow at its hand grip portion to a horizontal shaft, the bow being disposed generally perpendicular to the shaft. The shaft is mounted for rotation on a frame, which also supports a trigger spaced apart from the shaft a sufficient distance to engage the bowstring of the bow in fully drawn position. This arrangement allows the bow, when an arrow is fired, to return to its initial alignment. The shaft is mounted on a fixture that may be slid by engagement of bolts in slots of each side of the frame to adjust the shaft ends in the radial direction, and adjustable bolts coaxial with the shaft provide for adjustment in the actual direction. The trigger is secured to a plate that is slidably mounted on the end of the frame opposite the shaft. Adjustments in location of the trigger to accommodate different bowstrings are provided by bolts that ride in slots in support members on which the trigger-holding plate is mounted.