Currently, optical pumping by a high-power semiconductor laser diodes, diode arrays and matrices is widely used for solid-state lasers. The spectral bandwidth of diode lasers can be ~ 1 nm, which provide a good match with the absorption spectrum of the activator ion in the active medium of a solid-state laser. This pumping method became relevant after the advent of highly efficient (efficiency > 60%) semiconductor lasers. The aim of this work is to record the absorption spectrum for the ⁴I_9/2→⁴F_5/2 transition of Nd³⁺ ions. The optimum pump wavelength is determined based on the absorption spectrum. The technique used in this work to obtain the absorption spectrum of Nd³⁺ ions in Y₃Al₅O₁₂:Nd crystals is based on the temperature dependence of the radiation wavelength of a semiconductor laser diode. Also in the work, the temperature dependence of the semiconductor diode power and the generation threshold is investigated.