The optical transition probability of Nd3+ (0.5 mol%) doped lanthanum-modified lead zirconate titanate (PLZT) is investigated. The absolute intensities of its forced electric dipole transitions between 400nm and 1 000 nm were measured, from which we obtain three phenomenological parameters, Ω2 = 0.787 × 10-20 cm2, Ω4 = 1.182 ×10-20 cm2, and Ω6 = 1.042 × 10-20 cm2, according to the Judd-Ofelt theory. The radiation lifetime (346.9μs)of the 4F3/2 metastable state, the stimulated emission cross-section σij (2.49 × 10-21 cm2, 6.51 × 10-21 cm2,2.17 × 10-21 cm12) and the fluorescence branch ratios are calculated. We also measured the fluorescence lifetime(155.84μs) and calculated the quantum efficiency (46.1%). The analysis reveals that Nd3+-doped PLZT, based on its large electro-optical effect, has potential applications in active optical devices.