A crossbow includes a stock, a bow connected to the stock, a string connected to the bow, a string loader for loading the string, and a trigger and safety apparatus for controlling the string. The trigger and safety apparatus includes a trigger unit, a trigger safety unit and a string safety unit. Due to the use of the string safety unit, loading and locking of the string are synchronously executed, and loading of the arrow and disabling of the string safety unit are synchronously executed. The trigger safety unit is movable between a locking position and an unlocking position. In the locking position, the trigger safety unit unlocks the trigger unit.