The crystal structure of BaEu2Mn2O7 with a layered perovskite was determined for the powder X-ray diffraction data by Rietveld analysis. The unit cell is orthorhombic with a a(0) = 0.5503(1), b(0) = 0.5481(3), c(0) = 2.030(9) nm amd Z = 4 with the space group Fmmm. The oxygen octahedron in this Structure was elongated along c axis and distorted along [110](t) direction of fundamental body centered tetragonal cell due to Jahn-Teller effect.