Nariyuki MINAMI Theory of Point Processes and Some Basic Notions in Energy Level Statistics (125K, LaTeX 2e) ABSTRACT. Although it is not explicitly stated in physics literature, energy level statistics is based upon the hypothesis that the spectrum of a quantum Hamiltonian, after suitably normalized (unfolded), and observed in thermodynamic or semiclassical limit, looks like a typical realization of a stationary point process. In this survey article, we present a purely phenomenological view of energy level statistics based on the theory of point processes.