Display omitted •Novel bioactive composite scaffold with capability to release loaded platelet-derived growth factor in sustained manner was prepared.•Prepared composite scaffolds exhibited in vitro antibacterial and osteoconductive activities.•In vivo accelerated formation of cranial bone with prepared composite scaffold established their possible application in clinical settings. The repair of bone defects has long been a challenging and significant health question. Here, collagen hydrogel incorporating platelet-derived growth factor (PDGF)-loaded photopolymerizable ZIF-8-PDA nanoparticles (PDGF@ZIF-8-PDA@COL hydrogel) was prepared and perfused into 3D printed poly (lactide-co-glycolide)-tricalcium phosphate (PLGA-TCP) scaffolds. The resulting PDGF@ZIF-8-PDA@COL/PLGA-TCP composite scaffolds were applied as a bone substitute for cranial bone defect repair. The photopolymerizable ZIF-8-PDA nanoparticles had a mean size of 226.2 ± 5.3 nm with photothermal conversion capacity. PDGF@ZIF-8-PDA@COL/PLGA-TCP composite scaffolds showed a slower release of PDGF compared to PDGF release from collagen hydrogels. The composite scaffolds exhibited excellent antibacterial properties and good in vitro osteoconductive capacity. The osteoconductive activities of PDGF@ZIF-8-PDA@COL/PLGA-TCP composite scaffolds were also investigated in a rat cranial bone defect model in vivo by micro-CT imaging, hematoxylin and eosin staining, Masson’s trichrome staining, and immunohistochemical staining of osteogenesis-related markers. The PDGF@ZIF-8-PDA@COL/PLGA-TCP composite scaffolds accelerated cranial bone formation and gradually degraded over time. All these results provided strong evidence that PDGF@ZIF-8-PDA@COL/PLGA-TCP composite scaffolds might be a promising system for bone defect repair.