Nanotechnology is a fast growing area of research in various discipline carbon nitride vanadium oxide (C3N4 –V2O5) nanoparticles were synthesized by simple thermal decomposition method. Ultraviolet – Visible spectroscopy, Fourier transformed infrared spectroscopy (FT - IR), Raman spectroscopy x-ray diffraction (XRD) and Scanning electron microscopy (SEM) were employed to characterized the structure, light absorption capacity of the synthesized sample. The photocatalytic activity of C3N4– V2O5 nanoparticles was examined by using degradation of methylene blue (MB) as the model organic pollutant. The visible light irradiation of aqueous dye solution in presence of C3N4–V2O5 nanoparticles showed decrease in absorption maximum with shift in absorption maximum λ = 663nm. Further, absorbance of C3N4 – V2O5 Showed a maximum value of 0.37 before irradiation and decreased to a value of 0.05 after 120 min. It can seen that the C3N4 – V2O5 nanocomposite exhibits maximum efficiency towards the photocatalytic degradation of methylene blue. The electrochemical sensing properties of were studied using hydroquinone.