The kinetics of pulsed cathodoluminescence of Nd3+ ions in Nd:YAG single crystals and ceramic samples was studied. In these substances, luminescence appears after the ending of exposure by an electron beam with a duration of 2 ns. Optical transitions are observed from the 2F5/2 level and manifest themselves in the ultraviolet and visible regions of the spectrum, and from the 4F3/2 level - in the near infrared region. The kinetics of luminescence is characterized by a rise and a decay and is described by the difference between two exponential functions. It has been determined that the characteristic decay times of luminescence are the lifetimes of the 2F5/2 and 4F3/2 radiative levels, and the time of a rise is determined by the pumping mechanism. Moreover, the pumping of the uppermost Stark component of the 2F5/2 level occurs in the process of linear recombination of the ionized neodymium ion with free electrons, and the 4F3/2 level is due to nonradiative transitions from the upper levels.