The results of gasoline engine emissions purchased by the Toyota ANZ1 are statistically evaluated with the catalyst developed (La2O3/Zn/Na). The tests were carried out in the combustion test bench developed. The results show that the percentage of CO emissions increases as the engine speed increases, reaching values higher than 4%, with the original catalyst being that with the catalyst developed, which contains 5% by weight of Lanthane emissions of CO are close to 2%, but when the engine doesn't have the oxygen sensor. When the concentration of Lanthane is 7,5%, the efficiency reaches 7% of CO removal and 32% of HC removal. The statistical test T for independent samples indicates that the original catalyst and that developed presently a statistically significant difference in catalytic efficiency. On the contrary, when the oxygen sensor is connected, the catalyst developed is also efficient. On the other hand the emissions of HC decrease as the engine speed increases reaching values close to 200ppm which corresponds to the EURO III standard, being that with the catalyst developed, which contains 7,5% by weight of LNG, the HC emissions It is 147ppm showing good performance.