We report 73Ge-NMR measurement on the ferromagnetic superconductor UGe2 at ambient pressure. The observed NMR spectrum supports that the electric field gradient at three inequivalent Ge sites is correctly deduced by a LDA calculation. The temperature dependences of the nuclear spin lattice relaxation rate 1/T1 for H0⊥a (easy axis) and H0∥a were obtained for the oriented sample. The contrasting behavior in 1/T1 for H0⊥a and H0∥a reveals that the magnetic fluctuation of UGe2 is highly anisotropic.