Polymer fibers are finding increasing applications in commercial optical communication systems. Polymer optical fibers, with specified desirable consumer characteristics, can be computationally designed. Through the use of an extensive structure - property correlation database, properties of polymers can be predicted by a Neural Network. In this paper we are focusing on glass transition temperature (Tg) that influences a desired outcome in polymeric optical fibers. Performance of such fibers can be optimized by engineering a polymer to exhibit a lower refractive index and Tg. This paper compares and discusses a neural network model and a linear model that have been developed to correlate Tg and repeating units of polymers. A comprehensive neural network model with 28 descriptors was developed to predict T values of 6 g randomly selected polymers from a database containing 71 polymers. The network was trained with the remaining 65 polymers and had an average training RMSE of 17 K (R2 = 0.95) and prediction average error of 17 K (R2 =0.85) based on 10-time experiments. A linear regression model developed for comparison had an average error of 32 K (R2 = 0.81).