Ag nanoparticles decorated Polyaniline (PANI)/graphitic carbon nitride (g-C3N4) composite was fabricated as active electrode materials for supercapacitors via an in-situ oxidative polymerization. Morphology and structure of Ag/PANI/g-C3N4 composite were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) and X-ray diffraction (XRD). The supercapacitive behavior of the electrode material was tested in a three electrode system using 1.0 M H2SO4 electrolyte. The results indicated that the Ag/PANI/g-C3N4 composite delivered a high specific capacitance of 797.8 F g(-1) and an excellent capacitance retention of 84.43% after 1000 cycles at an applied current density of 1 A g(-1). Ragone plot was derived and compared which showed enhanced supercapacitive performance of Ag/PANI/g-C3N4. The composite should be ideal potential electrode materials for high-performance and effective supercapacitors.