This study evaluated the influence of Styrax camporum stems hydroalcoholic extract (SCHE) and of chemical markers of the genus, egonol (EG) and homoegonol (HE), on DNA damage induced in V79 cells by mutagens with different mechanisms of action. These natural products were combined with different mutagens [methyl methanesulfonate (MMS), hydrogen peroxide (H2O2), (S)-(+)-camptothecin (CPT), and etoposide (VP-16)] to evaluate the modulatory effect on DNA damage. The results showed that SCHE was genotoxic at the highest concentration tested (60 µg/mL). Treatment with EG or HE alone induced no genotoxic effect, while genotoxic activity was observed when the two compounds were combined. The SCHE extract was able to reduce the frequency of micronuclei induced by H2O2 and VP-16. Similar results were observed when the cell cultures were treated with EG and/or HE plus VP-16. In contrast, the highest concentration (40 µg/mL) SCHE potentiated DNA damage induced by VP-16. Neolignan EG alone or combined with HE also potentiated H2O2-induced genotoxicity. However, these natural products did not influence the frequency of DNA damage induced by MMS or CPT. Therefore, the influence of SCHE and of chemical markers (EG and HE) of the genus on the induction of DNA damage depends on the concentration tested and on the mutagen used.