The effect of dislocations on both integrated intensities and rocking‐curve half‐widths has been studied in an (n, −n) double‐crystal spectrometer arrangement on copper crystals of 103<N<108dislocations per cm2. The results show that the rocking curve provides a suitable means of characterization of the density and the type of dislocations in this range. The changes in half‐width of the rocking curve and the integrated intensity produced by the dislocations can be described satisfactorily by the model of independently scattering perfect crystal blocks up to a dislocation density of 2×105/cm2, and at higher dislocation densities, lattice tilts produced by the dislocations appear to be the main source of line broadening.