Speaking before a meeting of EU trade ministers in Berlin on Monday, he said that steelmaking, alongside the chemicals and raw materials industries were among the bloc's core competencies and needed to be preserved.
European producers have long worried that overseas production, especially in China, will render them uncompetitive. The European Commission has floated the idea of a tax on imports that are produced in an environmentally harmful manner.
"We don't want to abandon Europe's steelworkers, and we will not," Altmaier said on Monday.
(Reporting by Andreas Rinke; writing by Thomas Escritt; editing by Thomas Seythal)