A new temperature stable, low-loss, low sintering temperature microwave dielectric material Mg0.5Zn0.5TiNb2O8 was investigated for the first time. Single phase Mg0.5Zn0.5TiNb2O8 was obtained, and it showed Columbite structure which was tri-ixiolite structure. The variation trend of dielectric constant was in accordance with variation trend of relative density. When the sintering temperature was lower than 1120 degrees C, the Qf value increased with the increasing of relative density. When the sintering temperature was higher than 1120 degrees C, the Qf value decreased with the increasing of the unit cell volume. With the decrease of bond strength, the tf increased. The typical values of e=30.74, Qf=66900GHz, tf=-4.01 x 10(-6)/degrees C were obtained for Mg0.5Zn0.5TiNb2O8 sintered at 1120 degrees C for 6h.