The invention relates to the technical field of preparation of electronic components and devices and particularly relates to high temperature and pressure resistant PTC (Positive Temperature Coefficient) thermistor ceramics for heating and a production process thereof. The process comprises the steps of preparing a material A from BaCO3, TiO2, Y2O3 and CaCO3 through the processes of material preparation, pre-stirring, filtering for iron removal, cyclic stirring and grinding, filtering for iron removal, pressure-filtration dehydration, calcining synthesis and the like, preparing a material B from Pb3O4, TiO2 and Nb2O5 through the processes of material preparation, pre-stirring, filtering for iron removal, cyclic stirring and grinding, filtering for iron removal, pressure-filtration dehydration, calcining synthesis and the like, and preparing the high temperature and pressure resistant PTC thermistor ceramics from a mixture of the material A, the material B, SiO2 and adjuvants through the processes of material preparation, ball-milling material mixing, filtering for iron removal, cyclic stirring and grinding, filtering for iron removal, spray granulating and the like. The high temperature and pressure resistant PTC thermistor ceramics disclosed by the invention have the characteristics of uniform ingredient dispersion, uniform crystal grain size, higher voltage resistance, lower attenuation performance, higher alpha coefficient and the like.