The genus Tribulus belongs to family Zygophyllaceae, comprises about 20 species in the world. Its various parts contain a variety of chemical constituents which are medicinally important, such as flavonoids, flavonol glycosides, steroidal saponins, and alkaloids. Also the Zygophyllaceae family is a source of many biologically active photochemical with tremendous potential for medicinal uses. Secondary metabolites mainly alkaloids, amides and terpenes are reported from the various species of Tribulus which are of great economical and medicinal importance. This paper reports the isolation of various bioactive compounds from Tribulus terrestris. GC-MS analysis of Tribulus terrestris fruits methanol extract revealed the existence of the major compounds cyclotrisiloxane hexamethyl and Cyclotrisiloxane Octamethyl (36.01% and 28.64%). These phytochemicals were Interpreted on mass-spectrum GC-MS  which conducted using the database of Wiley 275 L. The antibacterial action of AgNPs against human pathogens, Streptococcus pneumoniae and Pseudomonas aeruginosa was recognized.