Abstract: A squeezed state of phonons and photons may have less quantum fluctuation than a coherent state. Compared to phonons or photons, the elementary excitations of the spin waves-magnons, are also bosons. Their Hamiltonian in a particle-number representation is similar to that of phonons or photons, and thus the squeezed state of magnons is possible to exist. The parameters characterizing the properties of materials can be calculated by measuring the quantum fluctuation of spin components in the laser field.