  We report the detection of TeV gamma-rays from the shell-type supernova
remnant RX J0852.0-4622 with data of 3.2 h of live time recorded with H.E.S.S.
in February 2004. An excess of (700 +/- 60) events from the whole remnant with
a significance of 12 sigma was found. The observed emission region is clearly
extended with a radius of the order of 1 degree and the spatial distribution of
the signal correlates with X-ray observations. The spectrum in the energy range
between 500 GeV and 15 TeV is well described by a power law with a photon index
of 2.1 +/- 0.1(stat) +/- 0.2(syst) and a differential flux at 1 TeV of (2.1 +/-
0.2(stat) +/- 0.6(syst)) 10^{-11} cm^{-2} s^{-1} TeV^{-1}. The integral flux
above 1 TeV was measured to be (1.9 +/- 0.3(stat) +/- 0.6(syst)) 10^{-11}
cm^{-2} s^{-1}, which is at the level of the flux of the Crab nebula at these
energies. More data are needed to draw firm conclusions on the magnetic field
in the remnant and the type of the particle population creating the TeV
gamma-rays.
