Adsorption isotherms and reflectance spectra of four different 2, 2'-cyanine dyes have been obtained for silver bromide grains of a known specific surface area. 1, 1'-diethyl-2, 2'-cyanine bromide having the shortest methine chain shows the J-band at high coverage of the dye on silver bromide surface. On the other hand the other three 2, 2'-cyanine dyes show the the H-band at high coverage.