This thesis investigates the brazing of aluminum alloy to zinc-coated steel, focusing on the role of zinc in interfacial bonding and on the effect of aluminum surface preparation. Different trials were carried out on an Al/Zn-coated steel system by varying surface treatments and brazing temperature while keeping the dwell time constant. The joints were characterized by optical microscopy, SEM-EDS, and BSE imaging to study interfacial continuity, morphology, composition, and phase distribution. The results show that bonding is mainly governed by Zn-rich and Al–Zn mixed interfacial regions rather than by direct aluminum–steel contact. The joint quality was strongly affected by local processing conditions, including excessive gaps, porosity, discontinuities, and heterogeneous zinc redistribution.