In this paper, the polarized absorption and fluorescence spectra of Nd 3+ ion in the BaCaBO 3F non-linear optical crystal have been investigated at room temperature. The Judd–Ofelt theory, extended to anisotropic system, has been applied to calculate the phenomenological intensity parameters, spontaneous transition probabilities, branching ratios and radiative lifetimes. The maximum emission cross-sections have been calculated to be 7.22 × 10 −20 cm 2 and 15.21 × 10 −20 cm 2 at 1068 nm for π- and σ-polarization using the Füchtbauer–Ladenburg (F–L) equation. The fluorescence lifetime of 4F 3/2 manifold is equal to 57.7 μs, and the quantum efficiency is 26.8%, which is higher than those of most of other borates. The potential of Nd 3+:BaCaBO 3F as a new self-frequency doubling laser crystal has also been evaluated preliminarily. Appreciable self-absorption at the second-harmonic wavelength of Nd 3+:BaCaBO 3F crystal should be considered for further laser operations.