The Moscow Gold, or alternatively Gold of the Republic, was 510 tonnes of gold, corresponding to 72.6% of the total gold reserves of the Bank of Spain, that were transferred from their original location in Madrid to the Soviet Union a few months after the outbreak of the Spanish Civil War. This transfer was made by order of the government of the Second Spanish Republic, presided over by Francisco Largo Caballero, through the initiative of his Minister of Finance, Juan Negrín. The term also encompasses the subsequent issues relating with the gold's sale to the USSR and the use of the funds obtained. The remaining quarter of the Bank's gold reserves, 193 tonnes, was transported and exchanged into currency in France, an operation which is also known by analogy as the "Paris Gold".

The Bank of Spain is the Spanish member of the Eurosystem and has been the monetary authority for Spain from 1874 to 1998, issuing the Spanish peseta. Since 2014, it has also been Spain's national competent authority within European Banking Supervision. It was originally established by Charles III in Madrid in 1782, as the Banco Nacional de San Carlos, and took its current name in 1856. Its activity is regulated by the Bank of Spain Autonomy Act. The bank doesn't translate its name to English but uses its Spanish name in all English communications.