Aim: Green synthesis of silver nanoparticles (AgNPs) was gained more importance comparative with other methods due to their salient features such as simplicity in procedure, non-toxic by-products, and cost effective; rapidity. Among the different types of nanoparticles, AgNPs have received more focus due to their unique antimicrobial properties. Materials and Methods: We successfully synthesized AgNPs from an aqueous flower extract of the Calliandra haematocephala plant for the first time. Thus, synthesized AgNPs were characterized by ultraviolet-visible spectroscopy and the surface Plasmon resonance peak was identified to be 451 nm. The key chemical features responsible for the reduction of silver nitrate to form AgNPs and the capping agents present in the flower extract were identified by Fourier-transform infrared spectroscopy. The synthesized AgNPs (0.1, 0.2, 0.3, 0.4, 0.5mM) were screened for antibacterial activity by cup-plate method and antioxidant activities by H2O2 Scavenging assay, and Phosphomolybdenum Method. Results: On phytochemical screening of aqueous flower extract of C. haematocephala, it was revealed that various phytoconstituents such as alkaloids, flavonoids, tannins, and saponins, and cardiac glycosides were present. The potent antibacterial and antioxidant activity were identified at 0.5 mM AgNPs solution. Conclusion: The overall results confirmed that aqueous flower extract of C. haematocephala plant possess good antibacterial and antioxidant activity.