SnSe is a robust candidate for thermoelectric applications due to its excellent ZT performance. We compare single crystal and polycrystalline SnSe in thermal and electrical properties. The single crystal is synthesized with Bridgeman method, while the polycrystalline is synthesized with melting and SPS. The thermoelectric properties of both materials are measured with four-probe method and laser flash method. The results show power factor of single crystal is twice higher than that of polycrystalline, and thermal conductivity of single crystal are also thrice higher at all temperature range, leading to comparable highest ZT of those two materials. The highest ZT single crystal is 0.65 at 823 K, and 0.5 at 923 K for polycrystalline. These findings yield a foundation for the systematic exploration of SnSe thermoelectric application.