Copper(I) bromide, also known as cuprous bromide, is a chemical compound. Its chemical formula is CuBr. It has copper and bromide ions in it. The copper is in its +1 oxidation state.

Copper(I) bromide is a colorless solid. It turns green when in air. It does not dissolve in water. It is a reducing agent.

Copper(I) bromide is made by reacting copper(II) bromide with any sulfite and any bromide salt. This reaction makes hydrogen bromide gas.

It is used in organic chemistry. It is used to make organic compounds that have copper in them.

• Copper(I) iodide
• Copper(I) chloride