The magnetic moment of the Iπ=252- isomeric state at 1106 keV in 179Hf was measured by the technique of low-temperature nuclear orientation. From the result μ(252)=(7.43+/-0.34)μN the value gl=1.08+/-0.05 for the effective proton g1 factor is deduced. RADIOACTIVITY 179Hfm, 177Lu. Measured γ(⊖) polarized nuclei, γγ(⊖, H). Deduced δ, μH, ωτ, μ, gl. 3He/4He refrigerator, Ge(Li) detectors.