Goal of the present research was to apply a solid state reaction route to fabricate bismuth layer-structured multiferroic ceramics described with the formula Bi5FeTi3O15 and reveal the influence of processing conditions on its crystal structure and phase composition. Simple oxide powders Bi2O3, TiO2 and Fe2O3 were used to fabricate Aurivillius-type bismuth layer-structured ferroelectrics. Pressureless sintering in ambient air was employed and the sintering temperature was TS = 900°C, TS = 1000°C and TS = 1040°C. The phase composition as well as crystal structure of ceramics sintered at various processing conditions was examined with powder X-ray diffraction method at room temperature. The Rietveld refinement method was applied for analysis of X-ray diffraction data. It was found that ceramics adopted orthorhombic structure Cmc21. The unit cell parameters of bismuth layer-structured multiferroic ceramics increased slightly with an increase in sintering temperature.