Today, wound healing is an important clinical problem that is often affected by microbial infection and not paying attention to this problem can cause irreparable damage to people. Biosynthesis of metal nanoparticles (NPs) has created a huge revolution in the field of nanomedicine due to their non-toxic, biocompatible, and stable characteristics. For this purpose, in this study, Petroselinum crispum seed extract (PCS) was applied to preparation of silver nanoparticles (AgNPs@PCS). The optimization of the silver nanoparticle synthesis involved adjusting the concentration of the silver salt, as well as the time and temperature parameters. After identifying the fabricated nanoparticles by FESEM, XRD, FT-IR, UV–Vis, TEM and EDS, their biological activity (like antibacterial, antifungal, antioxidant, anticancer, and wound treatment) was determined. The green synthesis of AgNPs was confirmed by several characteristics, including the surface plasmon response with a peak around 420 nm, the presence of both regular and heterogeneous sizes in the sample, and the observed color change from a clear solution to a brown color. The antimicrobial properties of the biofabricated AgNPs were investigated against fungal and various bacteria. The anticancer property of AgNPs@PCS was demonstrated by an IC50 value of 200 µg/ml after a 24-hour exposure on the MCF-7 cell line. Also, a dose-dependent antioxidant performance of AgNPs was found against the DPPH free radical. Histopathological evaluations of AgNPs@PCS ointment illustrated significant decrease in inflammatory cells. The results showed that vaseline ointment containing AgNPs@PCS prevented inflammation in the wound area and increased the number of fibroblast cells, which led to accelerated wound healing. Furthermore, in-vivo investigation showed the higher percentage of wound closure on days 7 and 14 was than the control group (Vaseline). Interestingly, the wound was completely closed after 21 days. Thus, we concluded that Petroselinum crispum-mediated silver nanoparticles show potential biological activity which can be used as nano-drug in clinical treatment.