This study investigated the sintering behavior of silver nanopastes at 150°C, 180°C, and 210°C. The synthesized silver nanoparticles were dispersed to form ink pastes with 70 wt. % and 80 wt. % silver. The morphology of the sintered silver nanopastes was studied via transmission electron microscopy (TEM), scanning electron microscopy, and x-ray diffraction analyses. Electrical characterization, thermal/humidity aging, and mechanical testing were also performed. Silver nanoparticles were prepared via a chemical reduction method. TEM images revealed particle sizes ranging from 10 nm to 20 nm. Results showed that electrical conductivity could be achieved at 150°C. When the sintered silver nanoparticles were subjected to 1000 h of 85°C/85 % relative humidity testing, a stable resistivity was achieved at a sintering temperature no lower than 210°C. These results showed that a stable network of sintered silver nanoparticles with good mechanical properties could be achieved at 210°C.