白铜（英语：Cupronickel），又称铜镍合金，是以镍为主要元素的铜镍锌合金，颜色为银白色，具有银色的外观但不包含银的元素，一般的成份是60％的铜、20％的镍和20％的锌。镍含量大约在10%至30%之间。镍含量更高的合金则被称为康铜。

白铜最早产于云南古堂琅县。后来在中亚的大夏曾用其铸造钱币，被认为是中国和大夏的交流产物。

由于白铜的强度坚硬和可塑性高、抗腐蚀性较好、电阻率较高、不生锈等性质，主要用于装饰品、给水器具、仪器器械和货币的制造。

Cupronickel (also known as copper-nickel) is an alloy of copper that contains nickel and strengthening elements, such as iron and manganese. Aside from the terms cupronickel and copper-nickel, several other terms have been used to describe the material: the tradenames Alpaka or Alpacca (registered trademark), Argentan Minargent, and the French term, Cuivre blanc, are still registered; cupronickel is also occasionally referred to as "hotel silver," plata alemana (Spanish for "German silver"), "German silver," and "Chinese silver".