A retractable leash with improved locking and unlocking mechanism, having a housing； a spool disposed inside the housing and biased towards the winding direction； a braking means； a locking means rotatable between a locking position to stop rotation of the spool towards the unwinding direction and an unlocking position； a biasing means which biases the locking means towards the unlocking position； a press button pivotable between a pressed position and a released position； an actuating means rotatably engaged with the press button and the locking means between a default position and an actuating position； and a sliding button having an upper portion exposing on the upper portion of the press button and a lower portion extending downwards through the press button into the housing.
