The curing of herpes simplex viruses 1 (HSV-1), and 2 (HSV-2) infections with the currently available synthetic therapies as Acyclovir often leads to the problems such as drug resistance and latency duration of the virus. However, studies based on alternative medicines showed that some of the natural products including medicinal plants have a therapeutic application and can be used as an antiviral agent. Thus, the current experiment aims to evaluate the antiretroviral activity of Cuminum cyminum seeds extract. In addition, the cytotoxicity and the antioxidant property of the extract of this plant using the DPPH free-radical assay were performed. The present study revealed that the seeds of C. cyminum contained a total phenolic content of 22.08 μg/mg (gallic acid equivalent dried extract) whereas, the flavonoid concentration was found to be 15.81 μg/mg (quercetin equivalents of flavonoids/mg dried extract). Furthermore, Cuminum cyminum seeds methanolic extract at 4 μg/ml provided 61% inhibition of plaque of HSV-1 and 49% inhibition of plaque of HSV-2. In addition, the results indicated that 137.4 μg/ml of the extract expressed 50% DPPH radical scavenging activity, thence suggesting the potential use of this seeds for treatment of the infection by these two viruses.