Langasite-type piezoelectric single crystal Sr3NbGa3Si2O14 (SNGS) 25 mm in diameter and 60 mm in length has been grown by the modified vertical Bridgman method. A < 0 0 1 >-oriented SNGS seed was used and the growth conditions were optimized. The dielectric constants of SNGS crystal show high temperature stability. With increased specific heat, SNGS crystal maintains a small internal temperature gradient when it works. The thermal diffusivity and thermal conductivity are as large as 0.54 mm(2)/s and 1.29 W/(m K) at 298 K, respectively. Thermal conductivity goes up with elevated temperature, and is slightly larger than that of Sr3Ga2Ge4O14 crystal. Small anisotropic thermal expansion was also observed in the SNGS crystal. These good properties indicate that the SNGS crystal has potential applications in high-temperature sensors and high power devices. (C) 2010 Elsevier BA/. All rights reserved.