High erosion of EDM electrode is a major concern for tool engineers working in electrical discharge machining (EDM) process. The machining cost and time are significantly affected by high erosion of tool and thus declines productivity of the process. In view of this, present work proposes a thermo-numerical model based on finite element method (FEM) for accurate prediction of two important performance measures for cryogenically treated EDM process viz. MRR and TWR. Open circuit voltage, pulse-on-time, duty factor, flushing pressure and brass electrodes subjected to different cryogenic soaking duration viz. 0 hrs, 24-hrs, 36-hrs are considered as important process variables for responses MRR and TWR while machining with Inconel 718 super alloy. A Box-bhenken design of response surface mythology (RSM) is adopted to reduce the number of experiments and extract maximum analysis from the study. It is observed that for the electrode treated with longer soaking duration (i.e. 36-hrs) wearing resistance is significantly improved due to enhancement of thermal properties owing to cryogenic treatments. Finally, a thermo- numerical model has been proposed to validate results obtained from the experimental results. The proposed model can be used to as a substitute to experimental methods to enhance the productivity for the cryogenically treated EDM process. © 2018 Elsevier Ltd. All rights reserved.