To provide a method for producing a ceramic sintered body suitable for producing a metal evaporation heating element in which the occurrence of cracks upon dry area generation is suppressed.

The method for producing a ceramic sintered body is provided by which raw material powder containing titanium diboride (TiB2) powder and boron nitride (BN) powder is molded then sintered in a nonoxidizing atmosphere. The method is characterized in that in the particle sizes by volume measured by a laser diffraction scattering type particle size distribution measurement device, the frequency of the region of 5 m is 15% to the whole region, the frequency of the region of 5 to 20 m is 75% to the whole region, and the frequency of the region of 20 to 62 m is 10% to the whole region. In the method, composition of the raw material powder preferably contains 40 to 60 pts.mass of TiB2, 31.5 to 58.9 pts.mass of BN, 0.3 to 2.0 pts.mass of AlN, 0.3 to 3.0 pts.mass of Sr compound and 0.5 to 3.5 pts.mass of Fe or Fe compound.