Abstract: Inner hybrid fiber reinforced plastics (IHFRP) sheets fabricated by PA,PET,and PPTA intermixing are adopted.Based on the experiment of concrete circular and quadrate columns confined by IHFRP under axial compression,failure configuration,stress-strain curve,bearing capacity,peak strain,elastic modulus,and ductility of such concrete columns are analyzed.Compared with the specimen without IHFRP,the bearing capacity and peak strain of the speciments with three or four layers of IHFRP are improved,respectively;With equal layers of fiber,the bearing capacity and peak strain of circular columns are higher than those of quadrate columns.With increasing radius at the corners augmenting,the bearing capacity and the peak strain of quadrate columns are improved at different levels.The ductility of concrete columns confined by IHFRP is estimated with the toughness index,which is figured with an area ratio of the load-compression strain.The I₂₀ of the confined columns is high,which indicates that there is excellent ductility at the latter reacting stage of concrete columns confined by IHFRP,and frame is better for seismic energy dissipation.