Graphene-based Ag nanocomposites are of specific interest because of their unique properties and applications, especially in the field of cytotoxicity. However, developing a simple method to synthesize reduced graphene oxide (rGO)/silver hexagonal nanoplate (Ag HNPT) (rGO–Ag HNPT) nanocomposites with well-defined morphology has been believed to be a major challenge. In this work, a facile, robust, and single-step synthesis method was developed to prepare silver-graphene (rGO–Ag HNPT) nanocomposites with hexagonal-structured silver nanoplates without any templates. The primary characterizations of the synthesized nanocomposite were done using a UV-visible spectrophotometer, X-ray diffraction (XRD), and Raman spectroscopy. The formation of uniformed hexagonal-shaped Ag nanoplates was confirmed by high-resolution transmission electron microscopy (HR-TEM), and the elemental composition was confirmed using energy dispersive X-ray analysis (EDX). With SiHa cervical cancer cells, the short-termin vitrocytotoxicity of the as-synthesized rGO–Ag HNPTs was evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The anticancer response of the rGO–Ag HNPTs was investigated using an MTT assay.