This study aimed to compare the diameter of sizes 25/.06, 30/.05, 35/.04, 40/.04 and 25/.07 main gutta-percha point of MTwo®system in relation to their corresponding nickel-titanium instruments. Material and methods: For this purpose, the measurements of both the main gutta-percha points and their corresponding instruments were obtained with the aid of a caliper at the positions D1, D3 and D11. Twenty points and six instruments of each size were used. Results: Data were subjected to student t test, with a significance level of 5%. It could be observed that there was a variation in the diameter of the gutta-percha points in relation to the diameter of the instruments. At D1 and D3, size 25/.07 points had diameters significantly higher than their respective instruments. At D11, sizes 25/.06, 25/.07, 30/.05 and 35/.04 points also had significantly higher diameters. For size 40/.04 point, there were no statistically significant differences between the point and instrument diameters. Conclusion:Most of the main gutta-percha points of MTwo® system analyzed in this study showed significantly greater diameters than those of their corresponding instruments. Only the size 40/.04 points did not present significant differences in diameter compared with their corresponding instrument.