A blend of polylactic acid resin and copolyester resin and a molded article using the same having superior impact resistance and heat resistance are disclosed. The blend of polylactic acid resin and copolyester resin includes: 5 to 95 weight % of polylactic acid resin; and 5 to 95 weight % of copolyester resin which is a copolymerization product of an acid component including terephthalic acid and a diol component including 5 to 99 mol % of 1,4-cyclohexanedimethanol and 1 to 60 mol % of isosorbide(bio monomer), and has a repeated structure of an acid moiety derived from the acid component and a diol moiety derived from the diol component.