This paper reports the second-order nonlinear optical (NLO) property of NaSb3F10, a potential new NLO material in the infrared region. The compound exhibits a phase-matchable second harmonic generation (SHG) efficiency of about 3.2 times that of KH2PO4 based on the powder SHG measurement. A measurement indicates that its laser damage threshold is as high as about 1.3 GW/cm2, which is much higher than all those IR NLO crystals reported in the literature. It also shows excellent transparency in the range of 0.25–7.8 μm with relativity high thermal stability. Single crystal of the size 12×10×8 mm3 has been grown in aqueous solution by a slow evaporation technique.