Abstract: The present invention provides an improved alumina sintered body on which a heater electrode is printed and which is sintered simultaneously with the heater electrode at temperatures lower than the optimum value 1,520.degree. C. The alumina sintered body includes high purity of alumina and 2 through 18% by weight partially stabilized zirconia, which further contains 2 through 6 mole percent solid solution of an oxide or oxides selected from Y.sub.2 O.sub.3, Sc.sub.2 O.sub.3, and lanthanum series metal oxides. The high purity of alumina may contain 0.1% by weight alkaline metals and/or alkaline earth metals and 1.0% by weight SiO.sub.2 at most. In the alumina sintered body of the invention, segregation and migration of impurities and chipping are effectively prevented and hence the durability of the sintered body is highly improved. Use of the alumina sintered body of the invention as a heater base makes the durability of a heater much longer.