Solid solution of the (1−x)PbZrO3−xBa(Al1/2Nb1/2)O3 system, with x = 0.02–0.30, was prepared using solid state reaction. The effect of Ba(Al1/2Nb1/2)O3 on phase transitions and thermal and electrical properties was investigated. The stability of ferroelectric phase in pure PZ was found to improve with increasing BAN content, which corresponded to the increased tolerance factor (t) of solid solution. In comparison to other systems, results in this study indicated that the tolerance factor can predict the ferroelectric (FE)/antiferroelectric (AFE) stability of PZ-based solid solution. If the t value of solid solution is higher than pure PZ, the FE phase can be induced. On the other hand, the AFE phase is stabilized when the t value of solid solution is lower than pure PZ.