Novel trivalent europium (Eu3+)-doped niobium oxyfluoride (Nb3O7F) nanomaterials with retarded carrier recombination and enhanced photocatalytic activity were successfully synthesized by a facile hydrothermal method. Through changing the doping ratio of Eu3+ ions, the phase, composition, morphology, absorption spectra and photocatalytic properties were investigated in detail. The results showed that Eu3+ ions were successfully incorporated into the interstitial sites of Nb3O7F crystal lattice. With the increase of Eu3+ amounts, the morphology gradually changed from nanowall to irregular nanoparticle. Meanwhile, incorporation of Eu3+ ions had a slight influence on the light absorption. However, Eu3+-doped samples exhibited excellent photodegradation activity towards Rhodamine B dyes. The improvement may be ascribed to higher specific surface area, and lower carrier recombination prohibited by forming Eu3+/Eu2+ self-redox centers. This work envisages that Eu3+-doped Nb3O7F nanomaterials may be a promising kind of photocatalysts.