Some important and essential features of naphthalene derivatives in water environment are studied. Possible interaction centers of investigated molecules with solvent are estimated Possible models of 1-naphthol, 1-naphtholate and prodan complexes in water are offered. The rate constants of photoprocesses and the quantum yield of fluorescence are determined for investigated molecules its complexes with water. Quantum-chemical calculations are performed in the geometry of both the ground and exited states of molecules.