The present study focused on the mushroom Ganoderma, which has been used in Eastern countries for centuries as a food and medicinal source. Specifically, the fruiting bodies of Ganoderma applanatum from the Kerala Forest Research Institute in Thirussur, Kerala, India, were analyzed for their nutritional and medicinal properties. The methanolic extracts of G. applanatum were used to examine secondary metabolites and proximate profiles, revealing the presence of various phytochemicals such as terpenoids, phenolics, glycosides, alkaloids, flavonoids, and saponins. Further analysis revealed the presence of significant amounts of calcium, sodium, phosphorus, and manganese. The compounds were characterized using chromatographic analysis, FTIR, and GC-MS, which revealed potential therapeutic compounds with C-H and C-O bonds in the amide group, β-glycosides, and C-C/C-O vibrations of phenolic substances. Mushroom extract at a concentration of 100 µg mL⁻¹ exhibited potent antimicrobial activity against various pathogens. This study suggests that G. applanatum has a rich biochemical composition and pharmacological potential, making it a promising candidate for drug development and traditional medicine, and contributes valuable insights into its diverse therapeutic applications.