Single-clove (SCG) and multi-clove (MCG) garlic exhibit marked differences in organosulfur compound profiles with direct implications for therapeutic use. GC-MS analysis revealed eight sulfur compounds in SCG and six in MCG. SCG was dominated by polysulfides, particularly hexathiane (30.56%), diallyl tetrasulfide (5.23%), and 5-methyl-1,2,3,4-tetrathiane (3.92%), alongside the heterocycle 3H-1,2-dithiole (4.93%). MCG was overwhelmingly characterized by diallyl disulfide (DADS, 46.22%), with trisulfides methyl 2-propenyl trisulfide (11.87%) and di-2-propenyl trisulfide (4.30%). SCG uniquely contained (Z)-1-propenyl disulfides (quinone reductase inducers, lipoxygenase inhibitors) and dimethyl trisulfide (anti-inflammatory, cyanide antidote). MCG’s high DADS content supports pleiotropic anticancer (apoptosis, anti-metastasis), anti-inflammatory (iNOS/COX-2 modulation), antimicrobial, and insecticidal activities. Hexathiane, the most abundant SCG compound, remains biologically understudied. These findings establish a functional dichotomy: SCG is preferable for chemoprotection, antioxidant defense, and emergency toxicology, whereas MCG is superior for cancer-directed, antimicrobial, and anti-inflammatory interventions. Garlic type selection for functional food or therapeutic applications should therefore align with the desired bioactivity profile.