Thespesia lampas has been used as medicinal plants for centuries to treat diseases and its antimicrobial therapeutic role has been well established. However, limited information is available about its activity against phytopathogens. The current study examined the methanol and chloroform extracts of T. lampas root extracts for polyphenols (total phenol and total flavonoid) through Folin-Ciocalteu, Aluminium chloride, and Phosphomolebdenum method. The antioxidant activity such as ABTS (2,20-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid), DPPH (2,2-diphenyl-1-picrylhydrazyl radical), and FRAP (Ferric ion reducing antioxidant potential)] were performed through the free radical scavenging method (ABTS & DPPH) and reducing power evaluation method (FRAP). Results of the study suggested that Methanol extract is superior to chloroform. Phytochemical screening of crude root extract proved the occurrence of steroids, flavonoids, terpenoids, alkaloids, and saponins. FTIR analysis of crude extract was carried out and the different functional groups were detected like O-H, C-H, -C=C-, C=O, C-N, and N-H suggesting the occurrence of several metabolites in the extract. From the GC-MS study, 16 major compounds were selected for docking study, among these, Copaene and Squalene confirmed the antimicrobial nature. The antimicrobial properties of extract were also confirmed against Xanthomonas oryzae pv. oryzae (Xoo), Magnaporthe oryzae(M. oryzae) and Xanthomonas axonopodis pv. glycines (Xag). Thus, T. lampas can be used as an important ingredient in agricultural formulations against various plant diseases.