In this work, studies of morphological and structural characteristics of BiOCl/AgX heterostructures (X = Cl, I) synthesized using ion-exchange reactions have been conducted. It was found that silver chloride (AgCl) crystals precipitating on the surface of bismuth oxychloride crystals show orientation ordering with the (001)BiOCl||(100)AgCl crystallographic relationship. Using two synthesis routes differing in the sequence of ion-exchange reactions, BiOCl/AgI heterostructures have been synthesized for the first time. It was shown that, in contrast to the BiOCl/AgCl system, silver iodide crystals precipitate on the basal planes of bismuth oxychloride without any preferred orientation. The synthesis strategy of bismuth oxychloride-based heterostructures proposed in this work can be used to synthesize bismuth oxyhalide-silver halide BiOX1/AgX2 (X1, X2 = Cl, Br, I) heterostructures of different compositions.