A new nonlinear optical (NLO) berate crystal Na3La2(BO3)(3) (sodium lanthanum berate, NLBO) has been discovered. The bar-shaped crystal with sizes up to 8 x 3 x 2 mm(3) was grown by the Top-Seeded Solution Growth (TSSG) method using Na2CO3-H3BO3-NaF as fluxes. The measurement of the infrared spectrum indicated that the basic anionic group is the BO3 group. Furthermore, NLBO crystal exhibits an optical second harmonic generation effect about twice as large as that of KDP(KH2PO4).