In this work, the thermal response of Mesocyclops ogunnus was experimentally studied. Temperature was the only one parameter that was tested. Other parameters, such as food quality and availability, light conditions, predation pressure, and water mass motions were not included in the study. Organisms were collected in Lake Kinneret and the experiments were carried out under diffused light, 12/12 hours light/dark conditions. In the experimental system, the organisms were exposed to different temperatures of 15℃, 25℃, 27℃, and 30℃ with open pathway to migrate according to temperature preference. The preference of upper thermal range (25℃, 27℃, 30℃) by copepodite and adult stages was documented.