Abstract: The fractal dimensions of zirconia phase were measured using the techniques of quantitative metallography under different conditions:the different percentage of zirconia,sintering temperature and sintering time. The results showed that the morphology of zirconia phase and grain growth of zirconia are described well by fractals and the mechanical properties of the composites were well correlated with the fractals of the zirconia phase distribution. So, the influence of the zirconia phase on the mechanical property can be quantitatively described by the fractal dimension.