Different theoretical methods estimating the formation enthalpy for hydrides have been adopted, among them the density functional theory (DFT) calculations. In this paper, an attempt has been made to study and estimate the formation enthalpy for CeH2, PrH2 and DyH2 hydrides, by mean of a datamining approach. Based on the data-sets selected from different published work, a principal component analysis (PCA) is applied to select the significant modeling inputs and simplify the model structure. An artificial neural network (ANN) with 3-13-1 architecture structure has been developed to estimate Delta H. The structural parameter and elastic properties of Ce, Pr, Dy, CeH2, PrH2 and DyH2 were calculated by the density functional theory (DFT+U). Also, the formation enthalpy of CeH2, PrH2 and DyH2 are determined. The results of Delta H calculated with both ANN and DFT+U are basically consistent and are in good agreement with the experimental data. The adopted ANN structure provided an advantageous technique in predicting the non-linear relationship between the formation enthalpy and its influences factors (a, R, chi) which were previously selected by PCA. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.