Electron Channeling Contrast Imaging (ECCI) is a nondestructive diffraction-based SEM technique that allows direct observations and comprehensive characterization of crystalline defects in the near-surface region (≈ 150 nm) of bulk materials. This technique takes advantage from the strong dependence between the backscattered electrons yield and the crystal orientation relative to the incident electron beam. Dislocations for example can be characterized by ECCI using the well-known transmission electron microscopy g•b=0 and g•b×u=0 extinction criteria where g is the diffraction vector and b the Burgers vector. In this study, fundamental and experimental aspects of electron diffraction for characterizing dislocation by ECCI in SEM are reported. The +g,-g method is explored on several dislocation configurations in an Interstitial-Free steel sample. Moreover, a detailed characterization of a dislocation dipole by ECCI is presented. obtained dipole is then an edge dislocation dipole in the 10-1 plane with [101] direction line.