(1-x)(Bi1/2Na1/2)TiO3-xBiAlO3 [BNTA100x (0 ≤ x ≤ 0.14)] ceramics were prepared by a conventional ceramic fabrication process. Single-phase perovskite structures were formed when x ≤ 0.08 for BNTA100x. The depolarization temperature, Td, at which piezoelectricity disappears, decreased with increasing x. The piezoelectric constant, d33, increased with increasing x because of the increase in free permittivity accompanied with decreasing Td. d33 and the electromechanical coupling factor, k33, of BNTA6 were 93 pC/N and 0.41, respectively. Normalized strain d33* (= Smax/Emax) at 60 kV/cm at the maximum field-induced strain was 122.2 pm/V for BNTA8. The value of d33* was higher than the calculated value of d33.