Abstract: A crossbow trigger mechanism is provided having three mechanically operable lever elements designated as a string holding cylinder, trigger lever and a locking lever. These three lever elements are mounted for pivotable rotation in a substantially common plane about parallel axes. Their axes are relatively positioned such that a mechanical interlock is formed between the cylinder and trigger lever when the cylinder is in a string holding position to prevent release of a string and between the trigger lever and locking lever when the locking lever is in a locking position with respect to the trigger lever to prevent the trigger lever from being moved. A torsion spring is provided and interconnected between the locking lever and trigger lever to provide a biasing force for rotation of the locking lever in either direction dependent upon whether the lever is in a locked position or an unlocked position.