This study examines the effects of abiotic stress conditions, including heat, drought, salinity, and chilling, on the accumulation of secondary metabolites, as well as the antioxidant and antimicrobial potential of Plectranthus amboinicus. The findings indicate that drought stress significantly increased the levels of phenolic compounds and tannins, whereas heat stress enhanced the accumulation of flavonoids and alkaloids. Salinity and low-temperature conditions also promoted the synthesis of phenolics and flavonoids. The antioxidant activity, assessed using the DPPH assay, demonstrated strong free radical scavenging ability, with IC₅₀ values of approximately 160 µg/ml. Furthermore, antimicrobial analysis showed effective inhibition of the bacterial strain Bacillus subtilis, with activity comparable to that of a standard antibiotic. Overall, the results suggest that exposure to abiotic stress enhances both the phytochemical profile and therapeutic potential of Plectranthus amboinicus, supporting its potential application in nutraceutical and pharmaceutical fields.