An algorithm for estimating the water quality parameters such as chlorophyll concentration, backscattering coefficient of particles and absorption coefficient of yellow substance from the irradiance reflectance observed just below the sea surface is developed and discussed with a view to application in optical remote sensing. In this algorithm, an optical model technique is coupled with the fluorescence technique. The computed water quality parameters are compared with those observed directly from concurrent surface water samples. In this comparison, efforts have been made to minimize the number of spectral irradiance reflectances used in the computation while ensuring that computed water quality parameters fit well to the observed ones. The results show that the observed water quality parameters can be closely represented by those computed from at least four selected wavelengths: 480, 520, 600 and 685 nm. Further, it has been observed that a similar approach utilizing three coastal zone color scanner (CZCS) bands 443, 520, and 620 nm, is applicable for interpretation of CZCS data. ¿ American Geophysical Union 1988