A composite ceramic body with increased strength is disclosed. The composite ceramic body, composed of a matrix of alumina particles with a mean particle diameter ranging from 0.7 to 1.8 μm and nano-zirconia particles with a particle diameter of 0.15 μm or less, wherein the alumina particles and the nano-zirconia particles fall in a respective weight percentage ratio ranging from 80:20 to 95:5 with a relative density of 93% or more and wherein in a cross section, a total sum of surface areas of pores, having cross-sectional areas equal to or greater than surface areas of circles having the same diameters as a mean particle diameter of the alumina particles, falls in a value of 2.2% or less based on a whole of the cross-sectional areas.