Poly(ether ether ketone)s containing allyl groups were prepared by nucleophilic substitution reaction of alkyl-substituted difluoro diaryl ethers with hydroquinone or by electrophilic substitution reaction of alkyl-substituted diaryl ether with 4,4’-oxydibenzoic acid in PPMA. Polycondensations proceeded smoothly and produced polymers having inherent viscosities up to 0.5-1.6 dL/g. The polymers were quite soluble in strong acid, dipolar aprotic solvents, and chloroform at room temperature. Thermogravimetry of the polymers showed excellent thermal stability, indicating that 10% weight loses of the polymers were observed in the range above 450 degrees C in nitrogen atmosphere. The glass transition temperatures of the polymers ranged from 128 to 146 degrees C. Furthermore, Polymer 3b functioned as a photosensitive resist of negative type for UV radiation. The resist had a sensitivity of 42 mJ/cm(2) and a contrast of 2.5, when it was postbaked at 100 degrees C for 10 min, followed by development with THF/acetone at room temperature.