An improved curable epoxy resin composition of a vicinalpolyepoxide and an effective amount of a novel polyether urea curing agent is disclosed. The improved curable epoxy resins which are useful as coatings, castings, sealants, and adhesives show improved tensile shear strength, flexural strength, and ultimate elongation. The novel polyether urea curing agents of the instant invention are characterized by terminal primary amino groups and are formed by reaction of polyoxyalkylenepolyamines with urea, urea forming compounds, or bifunctional isocyanates.A preferred curing agent includes a mixture of a novel polyether urea formed by reaction of a polyoxypropylenepolyamine having a molecular weight of from about 200-2000 and an effective amount of urea; and another known epoxy resin curing agent such as polyoxyalkylenepolyamine in ratios of from about 5:1 to 1:5 by weight.