We fabricated epitaxial thin films of hexagonal DyMnO 3 , which otherwise form in a bulk perovskite structure, via deposition on Pt(111)//Al 2 O 3 (0001) and YSZ (111) substrates: each of which has in-plane hexagonal symmetry. The polarization hysteresis loop demonstrated the existence of ferroelectricity in our hexagonal DyMnO 3 films at least below 70 K. The observed 2.2 µC/cm 2 remnant polarization at 25 K corresponded to a polarization enhancement by a factor of 10 compared to that of the bulk orthorhombic DyMnO 3 . Interestingly, this system showed an antiferroelectric-like feature in its hysteresis loop. Our hexagonal DyMnO 3 films showed an antiferromagnetic Néel temperature around 60 K and a spin reorientation transition around 40 K. We also found a clear hysteresis in the temperature dependence of the magnetization, which was measured after zero-field-cooling and field-cooling. This hysteresis may well have been of spin glass origin, which was likely to arise from the geometric frustration of antiferromagnetically-coupled Mn spins with an edge-sharing triangular lattice.