ABSTRACT： In the past few years, perylenediimide-cored (PDI-cored) dendrimers have been success-fully prepared and applied in various fields. In this review, we focus on the structuraldesign and synthesis strategies of PDI-cored dendrimers that involve convergent and diver-gent synthesis approaches. When building the outer shell of PDI-cored dendrimers, firsthydrophobic and then hydrophilic macromolecules are introduced. The advantages ofwater-soluble PDI-cored dendrimers include strong red fluorescence, excellent photostabil-ity, low cytotoxicity, high quantum yield, and versatile surface modification. The biologicalapplication of water-soluble PDI-cored dendrimers is broad, including fluorescence live-cell imaging, fluorescent labeling, and gene delivery, owing to the rapid development ofthese materials in the past decade. The challenges and outlooks in this field will also bediscussed.