The biology of the predacious mite, Neoseiclus warmer's Oudeman, was studied when fed on movable stages of two spotted spider mite, Tefranychus urficae Koch in Egypt for the first time. At 25 and 30°C and 65%*5% RH the incubation period lasted 3.7±0.1, 2.5±0.15, 3.2±0.1 and 2.4±0.13 days for female and male, respectively. The male emerged 0.5 day earlier than the female at 25°C, while at 30°C the male emerged 0.1 day earlier than the female. The female predator devoured 19.4±0.1 individuals of T urticae during the oviposition period (17.9 * 1.39 days) and deposited 14.3±1.6 eggs at 25°C, while at 30° the female predator devoured 20.2±0.2 individuals of T unticae during the oviposition period (18.5±0.2) and deposited 16.2±1.3 eggs.