There is provided a semiconductive ceramic sintered compact that has a conductivity high enough to attain static electricity removal and antistatic purposes and, at the same time, has excellent mechanical properties or stability over time. The semiconductive ceramic sintered compact includes at least a main phase and first and second phases contained in the main phase observed as a result of observation of any face of the sintered compact, the main phase being a ceramic sintered phase containing Al2O3 particles, the first phase being a grain boundary phase including a conductive substance-containing conductive phase and Al2O3 particles, the Al2O3 particles being present in an island-sea form in the conductive phase, the second phase being a grain boundary phase containing a conductive phase having the same composition as the conductive phase in the first phase and having a structure that electrically connects the first phases three-dimensionally to each other.