The first scientific flight of the BESS-Polar experiment was carried out in December 2004, aiming at elementary particle phenomena in the early Universe through observation of low energy antiprotons and search for antimatter in the cosmic radiation. The BESS-Polar payload was launched on December 13 from Williams Field near the US McMurdo Station in Antarctica, and circulated around the South Pole for 8 days and 17 hours. During the flight, the superconducting spectrometer including the solar-cell power supply system worked well, and two terabytes scientific data were recorded on the onboard hard disk drives. The flight was terminated on December 21, and the payload landed on the Ross Ice Shelf. The recovery operation continued for a week, and the spectrometer was recovered safely.