Abstract: An improved safety mechanism of a lighter contains an idle wheel with coarse grains, pivoted on two ratchet arms on the top end face of the lighter; a seat right below the idle wheel; a tension spring received within the seat and a flint bar provided between the tension spring and the idle wheel. The oval axle of the idle wheel of an oval shape is loosely inserted in a smaller hole at the upper portion of an egg shaped slot on the two ratchet arms, the portion of the egg shaped slot being bigger gradually downward. Upon lighting up, an appropriate counterbalance force against the spring tension is applied for the oval axle of the idle wheel to shift downward into the lower portion of the egg shaped slot and then the idle wheel may be rotated to rub against the flint bar to effect ignition.