This study on Buddleja polystachya highlights its phytochemical composition, antimicrobial activity, and cytotoxic impacts. The study emphasizes the plant’s potential to treat ocular diseases by identifying important compounds involved in the bioactivity through GC-MS analysis. This study explores the antimicrobial and cytotoxic potential of Buddleja polystachya (stem and leaves) extracts, with a focus on their application in treating bacterial ocular infections and their efficacy against MCF7, HT29, and HepG2 cancer cells. Through comprehensive GC-MS analysis, a diverse array of phytochemicals was identified within Buddleja polystachya stem and leaves extracts, including carbohydrates, phenolic derivatives, fatty acids, and steroidal components. The extracts were then evaluated for their biological activities, revealing significant antimicrobial properties against a range of bacterial strains implicated in ocular infections. The research findings demonstrate that stem extracts derived from Buddleja polystachya demonstrated high to moderate cytotoxic effects on cancer cell lines MCF7, HT29, and HepG2. Notably, these effects were characterized by varying IC50 values, which suggest distinct levels of sensitivity. In contrast, leaf extracts exhibited reduced cytotoxicity when tested against all these cell lines, although they did so with a significantly higher cytotoxicity aganist HepG2 cells. The results of this investigation highlight the potential therapeutic utilization of Buddleja polystachya extracts in the management of ocular infections and cancer. These results support the need for additional research to elucidate the underlying mechanisms of action of these extracts and explore their potential as drugs.