The U.S. dollar hit a record low against the euro of $1.22 in Monday trading and dropped to an 11-year low against the British pound and a three-year low against the Japanese yen.
Experts said currency traders were disappointed by Friday's report that the U.S. economy created fewer-than-expected jobs and worried that the U.S. central bank might signal an eventual interest rate hike when they meet on Tuesday.
Interest rates are currently at a 45-year low.
Low interest rates are helping the U.S. economy recover from a slump, but they mean investors can get higher returns in other countries, which reduces demand for the U.S. dollar.
Last August, the U.S. Federal Reserve said it would maintain the low interest policy for a "considerable period." Analysts say if the central bankers keep that policy at Tuesday's meeting, the dollar could weaken further.
The weaker U.S. currency boosts U.S. exports by making U.S. made-goods cheaper for foreigners.