The increasing resistance of microorganisms to conventional chemicals and drugs has prompted research into new biocides with broad-spectrum activity. Essential oils (EOs), derived from plants, are used in folk medicine and play a crucial role in plant protection. EOs contain a variety of secondary metabolites that can inhibit or slow the growth of bacteria, yeasts, and molds. This review discusses the activity of EOs against pathogenic bacteria, focusing on their mechanisms of action. Gram-negative bacteria are generally more resistant to EOs than Gram-positive bacteria due to differences in their cell wall structures. EOs can disrupt the cell membrane, alter the cytoplasmic membrane, and affect the transport of ions and ATP. Terpenes, terpenoids, and phenylpropenes are common components of EOs, each with distinct antimicrobial properties. Terpenes, such as p-cymene and limonene, have limited antimicrobial activity, while terpenoids like thymol and carvacrol exhibit significant antimicrobial effects by disrupting the cell membrane and altering membrane proteins. The antimicrobial activity of EOs is influenced by their chemical composition and the amount of individual components. EOs can affect the fatty acid profile of the cell membrane, leading to changes in membrane fluidity and rigidity. They can also interfere with protein synthesis and cell division, altering the expression of various proteins and enzymes. EOs can disrupt the production of ATP and ATPases, leading to a loss of intracellular ATP and membrane integrity. Metabolomics studies have shown that EOs can alter the metabolome of bacteria, affecting cellular processes such as glycolysis and fermentation. The morphology of bacteria can be altered by EOs, particularly rod-shaped bacteria being more sensitive than coccoid cells. EOs can cause swelling, disruption of the cell envelope, and changes in the external surface of the cell wall. Additionally, EOs have anti-quorum sensing (QS) activity, which can inhibit bacterial communication and reduce virulence factor expression. Overall, EOs and their components exhibit a range of antimicrobial mechanisms, including membrane disruption, protein interference, ATP inhibition, and metabolic disruption. These properties make EOs promising candidates for developing new therapeutic agents against pathogenic bacteria.The increasing resistance of microorganisms to conventional chemicals and drugs has prompted research into new biocides with broad-spectrum activity. Essential oils (EOs), derived from plants, are used in folk medicine and play a crucial role in plant protection. EOs contain a variety of secondary metabolites that can inhibit or slow the growth of bacteria, yeasts, and molds. This review discusses the activity of EOs against pathogenic bacteria, focusing on their mechanisms of action. Gram-negative bacteria are generally more resistant to EOs than Gram-positive bacteria due to differences in their cell wall structures. EOs can disrupt the cell membrane, alter the cytoplasmic membrane, and affect the transport of ions and ATP. Terpenes, terpenoids, and phenylpropenes are common components of EOs, each with distinct antimicrobial properties. Terpenes, such as p-cymene and limonene, have limited antimicrobial activity, while terpenoids like thymol and carvacrol exhibit significant antimicrobial effects by disrupting the cell membrane and altering membrane proteins. The antimicrobial activity of EOs is influenced by their chemical composition and the amount of individual components. EOs can affect the fatty acid profile of the cell membrane, leading to changes in membrane fluidity and rigidity. They can also interfere with protein synthesis and cell division, altering the expression of various proteins and enzymes. EOs can disrupt the production of ATP and ATPases, leading to a loss of intracellular ATP and membrane integrity. Metabolomics studies have shown that EOs can alter the metabolome of bacteria, affecting cellular processes such as glycolysis and fermentation. The morphology of bacteria can be altered by EOs, particularly rod-shaped bacteria being more sensitive than coccoid cells. EOs can cause swelling, disruption of the cell envelope, and changes in the external surface of the cell wall. Additionally, EOs have anti-quorum sensing (QS) activity, which can inhibit bacterial communication and reduce virulence factor expression. Overall, EOs and their components exhibit a range of antimicrobial mechanisms, including membrane disruption, protein interference, ATP inhibition, and metabolic disruption. These properties make EOs promising candidates for developing new therapeutic agents against pathogenic bacteria.