A mini, low-cost, pulsed semiconductor laser range finder is introduced in this paper. In this range finder, a constant fraction discriminator (CFD) and a time amplifier are used to reduce effectively the work error because of the changes of signal amplitude and the count error of crystal clock. It achieves a single-shot precision of better than ±7cm when the signal amplitude of the CFD in the range of 0.2~2.2V.