Nanocrystalline ZnSe films were prepared by the chemical bath deposition technique by varying the pH of the reaction bath from 9.2 to 10.6, and the physical properties of the annealed films were investigated. The x-ray diffraction profiles of the samples showed hexagonal structure of ZnSe nanocrystallites except for films deposited at pH 10.6. Strain was compressive, but became tensile with increase in pH. Topographical studies by atomic force microscopy showed a smooth surface of the samples deposited at higher pH and therefore low surface roughness. Optical studies revealed homogeneous grain shape and size. The thickness, grain size, and bandgap of the samples showed consistent results. The photoluminescence emission peaks occurred at the same wavelength for different pH values. The physical properties of the annealed samples seem to make them suitable for application as buffer layers in thin-film solar cells.