The aim of this study was to compare retention after mechanical fatigue test 5,400 cycles between two implant attachment systems, the Locator® and the Locator R-Tx®. Ten samples of each system were investigated for the retentive forces. The retentive forces before fatigue test and subsequently after 900, 1,800, 3,600, and 5,400 cycles simulated 3-year functional life were recorded. Instron universal testing machine was a measurement with a crosshead speed of 5 cm per minute and 3 mm vertical range (0.14 Hz frequency). Descriptive statistics was represented as means and standard deviations. The retentive forces of both systems across each cycle of the whole fatigue test were compared by independent t-test (α = 0.05). Both systems resulted in decreased retentive forces in the overall fatigue test. The retentive force of the Locator R-Tx® exhibited from baseline to 5,400 cycles with 19.24 ± 1.12 N to 10.70 ± 1.75 N accordingly, and the Locator® exhibited from 19.95 ± 0.78 N to 11.65 ± 0.94 N. Although, the retentive forces of the Locator® in each cycle were higher than the Locator R-Tx® through the whole fatigue test, both systems were not statistically significant different (P<0.05) in each cycle. In conclusion, retention of the Locator R-Tx® and the Locator® was not significantly different both initial retention and final retention within 5,400 cycles fatigue test representing 3-year functional life. The Locator R-Tx® was an innovation to replace the Locator®, and it had improved geometry and design. This study supported that the Locator R-Tx® could provide retention similar to the Locator® which was a standard and popular implant attachment in the world’s market.