In this work, SnSe thermoelectric (TE) single crystals with size of 100 x 50 x 15 mm(3) was grown by a Horizontal Bridgman method. The as-grown crystals had standard Pnma space group at room temperature and its measured stoichiometric ratio (Sn:Se) was nearly 1:1. Besides, polycrystalline SnSe was also prepared by a hot pressing technique for comparison. The largest power factor PFcrystal along (100) facet was 5.08 mu Wcm(-1) K-2 and the maximum PFcrystal perpendicular to pressure direction was only 2.01 mu Wcm(-1) K-2, which means the grain orientation has significant influence on the electrical properties of SnSe. The measured total thermal conductivity of polycrystalline SnSe (Ktot-polycrystal) was always lower than that of single-crystal SnSe(Ktot-crystal) during the whole temperature range except near the phase-transition temperature, and their smallest values were all reached 0.44 Wm(-1) K-1. Finally, single-crystal SnSe shows a peak ZT of 0.92, which is much excellent than that of polycrystalline SnSe (ZT = 0.5) around 793 K.