Lorentz microscopy was applied to the observation of magnetic domains in iron-gallium (Fe–Ga) alloys. Results did not show any link between the magnetic domains and the magnetostriction enhancement by Ga addition, but did reveal that the drastic decrease in magnetostriction for Fe–31.2 at. % Ga was due to the presence of large scale precipitates. Magnetic domain features did not change in the alloys of A2, D0₃, A2+D0₃,A2+B2+D0₃, and A2+fine scale precipitates. Large scale precipitates within the slow-cooled Fe–31.2 at. % Ga affected both the distribution and wall motion of magnetic domains.