In the solutions which are prepared by mixing zinc nitrate hexahydrate, strong ammonia and methenamine in water bath at 90 Centigrade, lamellate and granular zinc oxide films have grown on different substrates such as B270 glass, glass based PAA films, pure aluminum foil and aluminum based PAA films. Films microstructures were characterized by scanning electron microscope (SEM). The influences of substrate and pH on the films microstructure were analyzed. Results reflect that: Ammonia plays an important role in the growing competition of grainy crystal; the more concentration of ammonia, the more zinc oxide crystals grow into granular. Because of the high specific area and adsorption capacity, lacunaris zinc oxide films have great application perspective in gas sensor, catalyzed sorption and biochemistry.