The　corrosion　behaviors　of　Cu–7.42Sn–0.156P　and　Cu–5.78Sn–0.162P　alloys　in　different　solutions　were　investigated.　The　results　show　that　the　Cu–Sn–P　alloy　with　higher　Sn　content　exhibits　better　corrosion　resistance.　In　the　NaCl,　NaHCO3,　and　NaCl+NaHCO3　solutions,　compared　with　Cu–5.78Sn–0.162P　alloy,　the　corrosion　current　densities　of　Cu–7.42Sn–0.156P　alloy　are　reduced　by　25.2%,　36.9%,　and　34.5%,　and　the　polarization　resistances　are　increased　by　32.0%,　25.4%,　and　29.9%.　The　Cu–Sn–P　alloys　have　the　best　corrosion　resistance　in　the　NaHCO3　solution,　followed　by　the　NaCl　solution　and　the　worst　in　the　NaCl　+　NaHCO3　solution.　The　increase　of　Sn　is　helpful　to　improve　the　density　and　spalling　resistance　of　the　corrosion　film.　There　is　a　double-layer　structure　for　the　corrosion　film　of　Cu–Sn–P　alloy.　For　the　alloys　immersed　in　the　NaCl　solution　and　the　NaCl+NaHCO3　solutions,　the　corrosion　films　consisted　of　Cu2O,　CuO,　and　SnO2.　For　the　alloys　immersed　in　the　NaHCO3　solution,　the　corrosion　films　are　composed　of　Cu2O,　CuO,　SnO,　and　SnO2.　The　increase　of　Sn　content　in　the　alloy　can　increase　the　contents　of　Cu2O　and　SnO　in　the　corrosion　films.　©　2022　Wiley-VCH　GmbH.