We used cell-free culture filtrate of Pseudomonas aeruginosa as a reducing mediator of AgNO3 to silvernanoparticles (AgNPs) and possibly used as a potential anticancer agent against thyroid cancer cells (TPC1). The bio-generation of AgNPs was firmly established by taking a UV spectrum at 380-500 nm wavelength. The Fourier transform spectrum analysis reveals the association of alcohol, phenol and aromatic functional groups with P. aeruginosa synthesized AgNPs (Ps-AgNPs). By observing under transmission electron microscopy (TEM), the size and structure of the Ps-AgNPs were characterized as the size was 30-70 nm and spherical in shape. The concentration-dependent cytotoxicity of Ps-AgNPs on TPC1 cells was observed and IC50 value was calculated. The alteration of oxidative and antioxidant biomarkers in Ps-AgNPs treated cells were observed. The induced apoptosis was determined by staining the Ps-AgNPs treated cells with DCFH-DA, Rh-123 dye, Acridine Orange (AO) and ethidium bromide (EtBr). Increased level of intracellular reactive oxygen species (ROS) generation and decreased level of mitochondrial membrane potential was observed in Ps-AgNPs treated TPC1 cells. Moreover, the apoptotic morphological changes were explored, which indicates increased apoptosis by inducing cell membrane damage in Ps-AgNPs treated cells. This biogenic approach will enable an effective and significant improvement in nano-oncotherapy.