(Pb1-xSrx)TiO3 (PST) (x=0.25, 0.50) powders were synthesized by a mixed oxide solid-state reaction method under various calcination temperatures (600-1100oC). Powder samples were characterized using thermogravimetric (TGA), differential thermal analysis (DTA), x–ray diffractrometer (XRD) and scanning electron microscopy (SEM). The results showed that a single-phase of PST for x=0.25 and 0.50 powders was successfully obtained with a calcination condition of 950 oC for 2 h with a heating/cooling rate of 5oC/min. The TGA-DTA results corresponded to the XRD investigation. The lattice parameter a increased whilst the lattice parameter c decreased with increasing calcination temperatures. The tetragonality of powders decreased with an increase of calcination temperatures. The average particle size of the powders increased with the increase of calcination temperature.