We present an optical investigation of the crystal-field levels of the Nd3+ ion in Nd2BaZnO5 by a variety of different optical spectroscopic techniques. The complete fine structure of the first multiplets from I-4(9/2) to F-4(3/2) was identified using temperature-dependent photoluminescence and far-infrared reflectivity measurements. In addition, absorption measurements, photoluminescence excitation experiments, and photoluminescence self-absorption were used in order to assign levels up to 28 000 cm(-1). The results obtained with independent methods and on different samples are self-consistent. Additional luminescence and absorption lines in the spectra tentatively indicate two different Nd3+ sites. A comparison with Nd2BaCuO5 is also presented.