We report on passive Q-switching action induced by a few-layer MoTe2 saturable absorber in an Yb:YCa4O(BO3)3 (Yb:YCOB) microchip laser. With a sapphire-based few-layer MoTe2 incorporated into the 4 mm long plane-parallel resonator of the Yb:YCOB microchip laser, efficient stable passively Q-switched operation was achieved under output couplings of 40%-70%, producing, at an incident pump power of 5.0 W, an average output power of 1.58 W at a repetition rate of 704 kHz with a slope efficiency of 36%; the pulse energy and peak power were respectively 2.25 μJ and 40.8 W, while the shortest pulse duration obtained was 52 ns.