Al-Sn-Cu alloys are one of the promising materials to replace Babbitt alloys to meet the requirement of marine engines towards high speed and heavy load. In order to explore whether Al-20Sn-1Cu alloy or Al-40Sn-1Cu alloy is more suitable for the application of bearings, the mechanical property and tribological property were compared, and the effect mechanism of Sn content on the properties was also elucidated. Results show that the content of 40 wt. % Sn in Al-Sn-1Cu alloys is not positive to the hardness, ultimate tensile strength, plasticity and wear resistance, although less time is needed for Al-40Sn-1Cu to reach running-in period and the fluctuation in the friction coefficient with sliding time is smaller. The lower hardness of Al-40Sn-1Cu is ascribed to higher proportion of Sn phase whose hardness is lower. The ultimate tensile strength, plasticity and wear resistance of Al-40Sn-1Cu are impaired mainly by the network distribution of Sn phase along the grain boundaries and more large-sized Al2Cu particles. Not only the percentage of interface cracking at the interface of α-Al/Al2Cu increases from 13.6 % in worn Al-20Sn-1Cu alloy to 22.2 % in worn Al-40Sn-1Cu alloy, but also the percentage of cracking in Al2Cu particles increases from 4.5 % in Al-20Sn-1Cu alloy to 8.6 % in Al-40Sn-1Cu alloy. Compared with Al-20Sn-1Cu, the fatigue wear, abrasive wear, oxidation wear and adhesive wear of Al-40Sn-1Cu are aggravated, leading to inferior wear resistance. This investigation provides a theoretical basis to develop high-Sn aluminum alloys with excellent mechanical property and tribological property.