Engine knock is one of SI engines fundamental problems since its appearance limits the increase of engine efficiency. Engine knock is an uncontrolled combustion that can cause a significant mechanical damage to vital engine parts and it depends on numerous parameters, such as engine load, engine speed, air-fuel ratio, temperature and pressure of the mixture, etc. Due to its importance for the operation of Otto’s engine, the description and the prediction of the knock is a major challenge for development engineers. Since experimental research requires the use of an extremely expensive equipment and is very time-consuming, over the past few years engineering tools for the process analysis have been developed that significantly accelerate the engine development process. A new model of predicting engine knock has been developed at the Chair of IS Engines and Motor Vehicles, which includes the calculation of the temperature inhomogeneity of the unburned zone and the calculation of the detailed chemical kinetics of the auto-ignition of the used fuel. The model was validated at the standard operation of Otto engine, however was not validated in engine operation with the engine with higher EGR ratio. Since the EGR system has become an indispensable vehicle component along with other exhaust gas aftertreatment technologies, it is necessary to validate the model for prediction of knock in that operating mode. For this purpose, on the experimental engine at the Laboratory of Engines and Vehicles, 11 operating points were measured, which primarily differed in mass fraction of EGR and the intensity of the knock. In the experimental analysis, the MAPO indicator was used as a measure of intensity of the knock combustion. Validation of the model was performed by comparing the MAPO indicator value from the experiment and the intensity of knock combustion obtained by the simulation. Analysis of the results showed that the new model predicts the occurrence of knock combustion very well in the operation of engines with higher EGR ratio.