We report a mode-locked Alexandrite single pulse laser with cavity dumping. Mode locking was achieved by using an AOM and an EOM was used for Q-switching and cavity dumping. The instability of the single pulse laser energy output was reduced down to a tenth of that of the conventional single trigger system by introducing a novel double trigger system. The single pulse laser energy and pulse width were 100 mJ and 475 ps in multiple mode and 12.5 mJ and 275 ps in single mode, obtained without a laser amplifier.