The optical Stark effect in the B 2 Δ 5/2 ←X 2 Δ 5/2 (1–0)Q e/f (5/2) and P e/f (7/2) lines of nickel monohydride, 58 NiH, was recorded and analyzed to produce values for the permanent electric dipole moment, μ, of 2.44±0.02D and 0.36±0.02D for the X 2 Δ 5/2 and B 2 Δ 5/2 states, respectively. The values are in agreement with the previously determined values [J.A. Gray, S.F. Rice, R.W. Field, J. Chem. Phys. 82 (1985) 4717] and with the experimental error approximately a factor of five smaller. A comparison with theoretical predictions and other first-row transition metal monohydrides is given.