Pyronin B (PyB)-graphene oxide (GO) is reported for metal-ion sensing since it is based fluorescent sensor. PyB-GO nanocomposites are synthesized in aqueous solution by Ultrasonic Homogenizers. The structure of PyB-GO nanocomposites is characterized with X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, UV-vis spectroscopy and Fluorescence Microscopy. PyB-GO binary system are studied for the sensing ability in the detection of metal ions as a fluorescent sensor. It shows high sensitivity and selectivity for Fe3+ metal ions in aqueous medium as a result of the spectroscopic data.