In this study, the SI engine piston heat transfer is calculated. In order to simulate the combustion chamber heat transfer and the transient temperature of the piston, a resistor-capacitor model for wall temperature prediction is used. Twenty four heat transfer equations coupled with two-zonal combustion model were solved simultaneously, based on the resistor-capacitor thermal network model. The model predicts the wall temperature well. For each model parameter, an expression as a function of the engine geometry, operational parameters, and material properties were derived to make the model applicable to other similar engines. The simulations were performed writing a computer program on MATLAB and the results were validated using the experimental data of the EF7.TC engine.