PURPOSE: The titled copolymer almost free of problems such as stickiness in spite of its high content of a soft component, comprising specified polyester and polyether units.

CONSTITUTION: A polyether ester block copolymer comprising hard component- constituting polyester units of formula I (wherein G is a 2W6 C aliphatic glycol residue, or a 6W12 C alicyclic glycol residue, R is a 6W12 C aromatic dicarboxylic acid residue, and i is a number which represents an average degree of polymerization and is not smaller than 1) and soft component-constituting polyether units of formula II (wherein R is the same as above, E is a poly(oxyalkylene) glycol residue having an average MW of 500W6,000 and the ratio of C/O of 2.0W4.5, and j is a number which represents an average degree of polymerization and is not smaller than 1.3. Although the content of the soft component is high as compared with conventional polyether-ester block copolymer, this polyether- ester block copolymer consisting of the above combination is far lower in stickiness and can be used in the form of fiber, film, or molding.