Abstract: The objective of our study was to construct the obesity (OBESE) model based on the method of response function (MRF) approach which allows predicting the impact of the pre-treatment meanings of subjects' psychological variables on the outcome of CBT weight management program. A total of 104 patients (32 males and 72 females, mean age was 37.6+/-6.7 years) participated in the CBT weight management program. Control group was included. The data on psychological variables were used for the construction of the OBESE model, evaluation of its parameters and providing simulation experiments. Results: The results revealed that the OBESE model simulates the CBT outcome satisfactorily and simulation experiments demonstrated that it could be applied as a predictive tool for evaluating the outcome of CBT weight reduction program. The OBESE model could be applied as a helpful tool for health technology assessment undertaking to evaluate the evidence on combined cognitive-behavioral therapy to reduce weight.