马口铁（SPTE）是两面镀有锡的铁皮，即冷轧低碳薄钢板，可防锈、耐腐蚀、无毒、又名镀锡铁。主要用于制作金属包装，包括罐头食品、饮料、化工、医药、卫生、涂料、油漆、喷雾剂、化妆品瓶盖等。**受日本影响被称为白铁的板金、钣金常与马口铁有连带关系，台语中的白铁仔又常指不锈钢。

早在14世纪波希米亚就开始生产马口铁，主要用来制造餐具和水杯。1800年，英国人制造了长期保存食物的马口铁罐，1847年，美国人发明了制罐机器，从此马口铁的需求不断扩展，目前全世界每年生产的锡有约1/3以上用来制造马口铁。

Tinning is the process of thinly coating sheets of wrought iron or steel with tin, and the resulting product is known as tinplate. It is most often used to prevent rust.

While once more widely used, the primary use of tinplate now is the manufacture of tin cans. Formerly, tinplate was used for cheap pots, pans and other holloware. This kind of holloware was also known as tinware and the people who made it were tinplate workers.