Significance Optics is a unique platform to speed up computation, providing advantages especially for inherently parallel operations. Here we demonstrate an optical experiment enabling the simulation of a paradigmatic prototype model for statistical mechanics: the spin glass (SG). SGs are systems presenting all the aspects of complexity, such as many equilibrium states producing multiple relaxation times and nontrivial phenomenology. With the optical approach, the spin state is mapped on the mirrors of a fast adaptive optics device illuminated by a laser, and the energy calculation is performed by collecting the intensity after all the controlled light rays interfered in strongly scattering medium. The optical simulation enables beating the digital calculation in terms of speed for large-sized SG.