Thin films of poly(methyl methacrylate) (PMMA) were deposited by laser ablation using the fourth harmonic, at 266 nm, of a Nd-YAG laser. The temperature of the glass substrate during deposition was found to be critical in determining the morphology and molecular weight of the ablated films. When the temperature of the glass substrate was maintained below the glass transition, hazy films of low density and molecular weight were obtained. In contrast, above T-g the ablated material coalesced into a clear, denser film of high molecular weight and excellent adhesion to the glass. We suggest that pyrolytic decomposition and subsequent repolymerization are a plausible mechanism to the formation of PMMA films by laser ablation.