The effect of 350 keV He + ion irradiation with fluences Φ (ions cm - 2 ) on the anisotropy of the critical current density j c (Θ,H,Φ) of c-axis oriented YBa 2 Cu 3 O 7 - δ thin films is reported. Here, Θ is the angle between the c-axis and the direction of the external magnetic field μ 0 H =< 5 tesla. An almost isotropic decrease of critical current density due to the ion bombardment up to fluences Φ =< 4.0 x 10 1 4 cm - 2 is observed. This result is different from that cm found for irradiation with heavy ions at high energies, for which an anisotropic change of the critical current density is obtained with a maximum near the incident direction of the ion beam due to the formation of amorphous columnar defects. The angular dependence of the normalized current densities j c (Θ,H,Φ)/j c (0,H,Φ) exhibits a universal relation with a maximum at Θ = 90 o . Significant deviations from j c (0,H,Φ) towards larger values, however, occur only for angles above 40 o in contrast to the predictions of standard models. Similarly, the field dependence of the normalized current densities j c (Θ,H,Φ)/j c (Θ0,Φ) is found to be unaffected by the ion bombardment.