The effects of alkali-soluble resin containing carboxylated random copolymers on the film; structure and individual particle morphology of poly(n-butyl methacrylate) latex film have been studied using atomic force microscopy. More instances of disruption to regular packing of the particles in the latex film, e.g., vacancies, cracking, and dislocations in the regular arrays and domains of random arrangement of particles, were observed in the poly(n-butyl methacrylate) latex film containing alkali-soluble resin than in its absence. In addition, indentations of the tops of the individual latex particles on the film surface were observed. The extent of this occurrence increased with the concentration of the alkali-soluble resin, the annealing temperature, and its duration. The results were interpreted in terms of the different degree of fusion of the poly(n-butyl methacrylate) particles and layer of alkali-soluble resin adsorbed on them during the film formation process.