A complete set of elastic, piezoelectric, and dielectric constants of [011] c poled multidomain 0.24Pb(In 1/2 Nb 1/2 )O 3 –0.46Pb(Mg 1/3 Nb 2/3 )O 3 –0.30PbTiO 3 ternary single crystal has been determined using resonance and ultrasonic methods and the temperature dependence of the dielectric permittivity has been measured at 3 different frequencies. The experimental results revealed that this [011] c poled ternary single crystal has very large transverse piezoelectric coefficient d 32 =−1693 pC/N, transverse dielectric constant ε 11 /ε 0 ~7400 and a high electromechanical coupling factor k 32 ~90%. In addition, its coercive field is 2 times of that of the corresponding binary 0.69Pb(Mg 1/3 Nb 2/3 )O 3 –0.31PbTiO 3 single system with much better temperature stability. Therefore, the crystal is an excellent candidate for transverse mode electromechanical devices.