Diketopyrrolopyrrole (DPP) and its derivatives are commercially used dyes that have drawn great attention in recent years for applications in organic electronic/optical materials. These material studies cannot progress without further developments in the syntheses of the DPP family of molecules. In this review, recent progress in the syntheses of DPP derivatives is summarized in detail as well as the structure–property relationships of the derivatives, including the syntheses of DPP cores, N-functionalization reactions, and π-extensions on and along the DPP cores. Finally, existing problems and future perspectives of DPP-based derivatives are also discussed.