The homogeneous low-agglomerated and well crystallined MnZn ferrite powder with good magnetic properties were prepared by coprecipitation method and adding dispersant. Effect of calcinations temperature on the properties such as XRD patterns, saturation magnetization intensity, hysteresis loop was investigated. The effect of the ratio of metal salts on saturation magnetization intensity, hysteresis loop was also studied. The results show that the increase of calcinations temperature is good for the formation of spinel MnZn ferrite and the promotion of magnetic properties. The best magnetic property is obtained when the ratio of Zn element is at a certain amount.