Tb 3+ doped Na 3 La 9 O 3 (BO 3 ) 8 (Tb:NLBO) crystals have been grown by the top-seeded solution growth (TSSG) method. X-ray powder diffraction results show that the introduction of Tb 3+ does not change the structure of NLBO crystal. Tb 3+ concentration was determined by inductively coupled plasma optical emission spectrometry to be 1.089×10 21 ions/cm 3 . The absorption and emission spectra were measured at room temperature by using a (1 0 0) oriented crystal wafer. According to the Judd–Ofelt theory, the spontaneous transition probabilities, fluorescence branch ratio, and the radiation lifetime of 5 D 4 state were calculated. The unpolarized and polarized emission properties under the 367 nm excitation were evaluated. The decay time of the 543 nm emission assigned to the 5 D 4 – 7 F 5 transition was also measured. All the results show that Tb:NLBO crystal would be a promising green laser material. [ABSTRACT FROM AUTHOR]