The influence of plastic deformation upon the linear magnetostriction of hard‐worked nickel has been determined by use of direct measurements of strain in three normal directions and then by measurement of magnetostriction in the same three directions using the method of rotating the specimen 90° for each measurement. This combination of measurements appears to have advantages for the interpretation of magnetostriction in nonisotropic bodies.The value of magnetostriction at saturation for gradeAnickel plastically deformed with an 84% reduction of cross‐sectional area was found to be −33.5±1×10−6. This compares with −35±1×10−6for annealed nickel of the same quality. The hard‐worked nickel was free of volume magnetostriction of determinable magnitude. It showed inappreciable preferred domain orientation. It did appear to have a small amount of preferred crystalline orientation.