"Gold bug" (sometimes spelled "goldbug") is a term frequently employed in the financial sector and among economists in reference to persons who are extremely bullish on the commodity gold as an investment or a standard for measuring wealth. Depending on the circumstances the term can have one or a combination of closely related and often overlapping themes that extend beyond the support for gold as an investment, including in some cases the use of the term as a pejorative.

The concept, in the second sense, was popularized in the 1896 U.S. presidential election, when William McKinley supporters took to wearing gold lapel pins, gold neckties, and gold headbands in a demonstration of support for gold against the "silver menace".