The rise of bacterial resistance to currently employed antibiotics is causing growing concerns for public health. The emergence of highly resistant bacterial strains results in the ineffectiveness of antibiotic treatments against many bacterial infections. As a result, there is an ongoing quest for new antimicrobial agents. This pursuit can take two main directions: one involves the design and synthesis of novel agents, while the other involves exploring natural sources to uncover previously undiscovered antimicrobial compounds. Herbal medications, particularly, have garnered renewed interest due to the perception that they tend to cause fewer adverse reactions when compared to synthetic pharmaceuticals. Moreover, the lower costs of producing plant-based preparations make searching for natural therapeutics appealing. This study aims to assess the antimicrobial properties of Thuja occidentalis (TO) and Platycladus orientalis (PO) against Gram-positive and Gram-negative bacteria using specified reference strains: Streptococcus pyogenes (ATCC 19615), Staphylococcus aureus (ATCC 25923), Listeria monocytogenes (ATCC 19114), Bacillus cereus (ATCC 10876), Clostridium perfringens (ATCC 13124), Shigella flexneri (ATCC 12022), Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922), Salmonella typhimurium (ATCC 14028) and Haemophilus influenzae type B (ATCC 10211) Additionally, we determined the minimum inhibitory concentration (MIC). Following ISO 20776-1:2019 guidelines, we assessed the antimicrobial activity by measuring the reduction in microbial mass through spectrophotometry to determine changes in optical density (OD). Our findings indicate that the TO and PO extracts inhibit Gram-positive bacteria, particularly at the initial concentration tested.