The Burgers vector of dislocations in the quasicrystalline Al–Cu–Fe icosahedral phase has been studied by means of diffraction contrast analyses and defocused convergent-beam electron diffraction. The size of the Burgers vector in real space is found to be 0·307 nm. This is the first observation of strain field amplitudes induced by dislocations in the quasicrystalline icosahedral phase.