Abstract: We proposed the spiron wave equation of free and nonfree photons, and gave the spin operator and spin wave functions of photon. By calculating the helicity of photon, we proved that there were lefthanded and righthanded photon. With the spin wave functions of single photon, we obtained the spin wave functions of two photons or multiplephotons, and gave spin entanglement state of multiplephotons.

Key words: spin operator, spin wave function； spin entanglement state, spiron equation of photon