Platelet-rich fibrin (PRF), which is the rich source of growth factors, has been used as an efficient scaffold in tissue regeneration. In this study, tannic acid as a green crosslinker with different concentrations (0.5%,1%,5%, and 10%) was used to improve the properties of PRF. The crosslinked gel scaffolds were evaluated by analyses such as SEM, FTIR, swelling and degradation, mechanical strength, cell toxicity, cell adhesion, and antibacterial test. The results showed that the scaffold structure changes by increasing crosslinker concentration. The swelling rate decreased from 49% to 5% for samples without the crosslinker and with tannic acid (10%), respectively. A decrease in the degradation rate was shown by increasing the crosslinker concentration. The mechanical strength of the scaffold with the crosslinker increased up to three times. Cytotoxicity was not observed up to 10% crosslinker concentration. The cells proliferated well on the cross-linked scaffolds and also showed a good antibacterial effect. In general, tannic acid can improve the physical and mechanical properties of PRF without negatively affecting its biological properties.