A piezoelectric lighter incorporates with a safety arrangement which includes is movably mounted on a casing in a vertical movable manner wherein a guiding slot is provided on top of the casing to communicate with an exterior thereof. A locking member includes a locking arm disposed in the ignition cavity and an operation button slidably mounted on an ignition button. A resilient element is adapted for applying an urging pressure against the locking arm so as to normally retain the locking arm in a locking position. In which, in the locking position, the locking arm blocks up the ignition button from ignition. In order to ignite the piezoelectric lighter, a user's thumb must operate the operation button for moving the locking arm to an unlocking position. Then, the user is able to push the ignition button downwardly to ignite the piezoelectric lighter.