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This study focused on testing the antibacterial and antifungal activity of <i>Origanum syriacum</i> (<i>O. syriacum</i>) and <i>Cimbopogon winterianus</i> (<i>C. winterianus</i>) extracts and their essential oils (EOs). The bacteria were isolated from urine samples and identified by a VITEK assay, and the fungi were isolated from spoiled food samples and further identified by MALDI-TOF. The susceptibility of the microbial isolates was assessed by determining the bacteriostatic and bactericidal/fungicidal effects by the minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC) broth microdilution assay and time-kill test. The antibiofilm activities were assessed by the antibiofilm screening assays. The bacterial isolates included three Gram-negative isolates (<i>Escherichia coli</i>, <i>Klebsiella pneumonia</i>, and <i>Citrobacter freundii</i>) and two Gram-positive isolates (<i>Staphylococcus aureus</i> and <i>Streptococcus intermedius</i>). The fungal isolates included <i>Candida albicans</i> and <i>Aspergillus niger</i>. The <i>O. syriacum</i> and <i>C. winterianus</i> extracts exhibited bacteriostatic and fungistatic activities (MIC 1.25–2.5 mg/mL for the bacterial isolates and 2.5–5 mg/mL for the fungal isolates). However, their EOs exhibited bactericidal (MBC 5–20%) and fungicidal (MFC 1.25–10%) activities, meaning that the EOs had a better antimicrobial potential than the extracts. The antibiofilm activities of the mentioned extracts and their EOs were relatively weak. The <i>O. syriacum</i> extract inhibited <i>S. aureus</i>, <i>S. intermedius</i>, and <i>K. pneumonia</i> biofilms at a concentration of 0.3125 mg/mL and <i>C. albicans</i> and <i>A. niger</i> biofilms at 0.625 mg/mL. No antibiofilm activity was recorded for <i>C. winterianus</i> extract. In addition, the packaging of grapes with <i>C. winterianus</i> extract preserved them for about 40 days. The results reflect the significant antimicrobial activity of <i>O. syriacum</i> and <i>C. winterianus</i> extracts and their EOs, thus suggesting their potential in food packaging and preservation.