Magnetic properties of Mn5Ge3C0.7 thin films grown by molecular beam epitaxy have been studied. SQUID-VSM measurements and magnetic force microscopy have been used to probe the magnetic state and determine the relevant magnetic parameters. The results are supported by a combination of improved Saito's and Kittel's models. The moderate perpendicular magnetic anisotropy (Q(exp) - 2K(u)/mu M-0(Sat)2 approximate to 0:2) leads to a stripe domain structure for film thicknesses above 28 nm. For thinner films, the magnetization lies in-plane. The uniaxial magnetocrystalline constant has been found to be much weaker than in Mn5Ge3 and is assigned to hybridization effect between the Mn and C atoms.