<p>The present study investigates the use of parsley leaf extract as a green-reducing agent for the production of reduced graphene oxide (rGO) from graphene oxide (GO), which was prepared using the improved Hummers method. The successful reduction of GO was verified through various characterization methods, including FTIR, XRD, DSC, UV, and zeta potential analyses, which revealed notable changes in the structural and thermal characteristics of the resulting material. The reduction process and the removal of oxygen-containing groups were confirmed utilizing FTIR and XRD analyses, while DSC analysis highlighted the thermal differences between GO and rGO. LC–MS/MS analyses identified the key phenolic compounds present in the parsley leaf extract responsible for the reduction process. Biological evaluations demonstrated that both GO and rGO were biocompatible, with rGO exhibiting notable anticancer activity against colon and breast cancer cells, including a 70% reduction in cell viability and significant apoptotic effects. Genotoxicity tests demonstrated that while GO exhibited mild genotoxic effects, rGO was non-genotoxic, indicating its suitability for biological applications. The effectiveness of rGO in both eliminating oxidative damage and accelerating the wound healing process was also clearly demonstrated in the oxidative damage test and scratch assay. These findings illustrate that parsley leaf extract is an efficient, environmentally benign reducing agent for producing rGO with promising potential for cancer therapy and other biomedical applications.</p> Graphical abstract <p></p>