Novel azobenzene-containing block copolymers (BCs) with a polyester block bearing azobenzene moieties in the side chain and a poly (methyl methacrylate) (PMMA) block have been synthesized by the combination of atom transfer radical polymerization (ATRP), polycondensation, and “click” chemistry. Two azide-terminated polyesters with different molecular weight (obtained by polycondensation) were coupled to an alkyne-functionalized PMMA (obtained by ATRP). Blends of the BC with the highest azo content (wt%) and an azopolyester homopolymer were also prepared. All these compounds were investigated by polarized light optical microscopy (POM), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM). Polarized light-induced anisotropy was studied by birefringence and dichroism measurements.