This paper deals with an experimental study on the friction torque characteristics of magnetic fluid seals for various oil temperatures, rotating speeds, and vacuum pressures. The friction torque of MFS was measured by high response torque meter. The experimental results show that, as the rotating speed increases, the friction torque of MFS increases and as the oil temperature increases, the friction torque of MFS decreases. Also, the experimental results show that the friction torque of Model-II is 1.73~2.56, 2.0~2.89, 2.0~3.25 times higher than those of Model-I under the atmospheric pressure, vacuum pressure ($10^{-4} and 10^{-6}$ torr), respectively.