Abstract: The purpose of this study was to understand the mechanisms through which an ambush predatory copepod, Megacyclops formosanus (Harada, 1931), captures mosquito larvae of Aedes aegypti. Fast-cam filming was used to study the predation mechanism of the ambush predator, M. formosanus, on Ae. aegypti mosquito larvae. Our study indicated that M. formosanus demonstrated 2 intermediate steps: aiming and stalking. Currently, intermediate predation steps are either ignored or not described for predatory copepods. The copepod’s aiming/stalking distance varied at about 4-8 body lengths, whereas the attack distance was shorter than the aiming distance. The stalking speed was significantly slower than the attack speed. Copepods preferred a cone-shaped area in front of the 1st antenna for attack compared to behind the antenna. In conclusion, both intermediate steps, aiming and stalking, enhanced the predatory success of an ambush predatory copepod by targeting prey for a sudden attack.