The present study aims to elucidate the chemical characterization of the methanolic extracts of Coleus blumei, Plectranthus amboinicus, and Salvia splendens with emphasis on their antioxidant, antifungal, and cytotoxic activities. Among all methanolic extracts, P. amboinicus extract containsthe highest contents of the total polyphenols and total flavonoids by 122.2 g GAE Kg^-1 and 41.4 g QE Kg^-1, respectively. Rosmarinic acid (1.021 g Kg^-1) was the predominant phenol in P. amboinicus according to HPLC analysis. Carvacrol was the predominant component (7.59%) of P.amboinicus extract by GC-MS analysis. The extract of P. amboinicus recorded the lowest IC₅₀ and EC₅₀ values for DPPH and reducing power by 0.042 g L^-1, and 0.327 g L^-1, respectively, indicating the greatest antioxidant potential. Also, P. amboinicus showed the highest antitumor activity using A549, MCF7, and HEPG cell lines with IC₅₀ values by 0.041, 0.047 and 0.043 g L^-1, respectively. Theextract of S. splendens showed a remarkable selectivity toward MCF7 cell line with IC₅₀ valueby 0.040 g L^-1.The methanol extract of P. amboinicus displayed the greatest inhibition on the mycelial growth of Sclerotinia sclerotiorum (83.0 %), Cochliobolus cynodontis (82.1 %), Botrytis cinerea(77.8 %), Bipolaris hawaiensis (74.1 %), B. spicifera (73.9 %), and Alternaria alternata (73.7 %) at the concentration of 32 g L^-1.