Background: Repeated implantation failure (RIF) refers to the condition where high quality embryos are unable to successfully implant after multiple cycles of in vitro fertilization (IVF) treatment. The aim of this study is to investigate the impact of intrauterine granulocyte colony-stimulating factor (G-CSF) and platelet-rich plasma (PRP) on pregnancy rate in patients with RIF., Materials and Methods: The present randomised clinical trial study was conducted at the IVF Centre of Mehr Medical Institute in Rasht, Iran, from 2020 to 2022. The research consisted of 200 individuals who had experienced multiple failed cycles. These patients were randomised into two groups: intrauterine infusion of 1 ml of G-CSF and intrauterine infusion of 1 ml autologous PRP at least 48 hours before embryo transfer (ET). The groups were compared in terms of implantation rate, and chemical, clinical, and ongoing pregnancy., Results: The implantation rate was significantly higher in patients who received PRP (P=0.016). Chemical pregnancy in the PRP group was significantly higher than G-CSF group (P=0.003). Both clinical pregnancy and ongoing pregnancy rates were significantly higher in the PRP group (P=0.001) compared to the G-CSF group (P=0.02)., Conclusion: The utilisation of PRP via intrauterine infusion is considerably more successful than G-CSF in enhancing pregnancy and live birth rates among patients with RIF.