Research in polymer gel is very popular recently, for instance, polyacrylamide (PAM). PAM gels are well-known for their highly water-absorbent properties. They are usually used as thickeners, suspending agents, soil erosion control reagents etc. In this study we investigated effects of the pH value of PAM solution and the charge density of PAM on morphologies of PAM films. Morphologies of PAM films adsorbed onto the glass surface were obtained with an atomic force microscope (AFM). The experimental results indicated that morphologies of PAM films might vary strongly with acidities of PAM solutions. The base-treated PAM formed tassel-like patterns, the acid-treated PAM existed as grains of various sizes, and the as-received PAM had uniform small ball-like shape. A film flow model was used to explain the experimental results.