A new microring resonator system is proposed for the detection of the Salmonella bacterium in drinking water, which is made up of SiO<inf>2</inf>-TiO<inf>2</inf> waveguide embedded inside thin film layer of the flagellin. The change in refractive index due to the binding of the Salmonella bacterium with flagellin layer causes a shift in the output signal wavelength and the variation in through and drop port's intensities, which leads to the detection of Salmonella bacterium in drinking water. The sensitivity of proposed sensor for detecting of Salmonella bacterium in water solution is 149 nm/RIU and the limit of detection is 7 × 10<sup>-4</sup>RIU.
