The target of the paper is the “greening” of the spark ignition engine by hydrogen fueling, knowing the potential of hydrogen to contribute in ecologically point of view to a CO2 neutral society. In the year 2030, it is considered that blue hydrogen has an exponentially increased potential compared to classical energy sources. Hydrogen is considered the ideal fuel of the future because it does not contain carbon, it isn`t toxic, has suitable properties for high efficiency use in combustion processes, can be stored and transported, representing an important energy vector. The A15MF spark ignition engine was tested under hydrogen fueling conditions, operating the engine at 55% load and a speed of 2500 rev/min, while collecting 250 individual pressure diagrams. The hourly consumption of the two fuels, gasoline and hydrogen, the level of pollutant emissions and greenhouse gases were measured for experimental study of the combustion. When using hydrogen, in energetically share of 2.55% and lean mixtures, lambda 1.18, the pressure during combustion begins to grow, with the increase of the maximum of pressure rise rate. The combustion process takes place faster and a rise in the heat release rate was observed. The effective specific energy consumption is reduced, the effective yield being improved when using hydrogen. Compared to fueling with gasoline, when fueling with hydrogen, the level of NOx emission is reduced 2.5 times, and that of HC emission too. The CO2 emission level is reduced by about 30% as a result of the improvement of the combustion process when using hydrogen.