Metallic (1T) molybdenum disulphide (MoS2) is a promising electrode material in the electrochemical energy storage application due to its excellent electrical conductivity and ionic intercalation property. Here, we report the metallic MoS2 modified with porous graphitic carbon nitride (g-C3N4) as a novel nanocomposite for efficient supercapattery electrode. The 1T-MoS2 is grown on the surface of porous g-C3N4, and thus it facilitates easier ion intercalation between these two materials. The prepared electrode of g-C3N4/MoS2 composite attained a maximum specific capacity of 515 C g−1 at 1 A g−1 current density and obtained 66% capacitive retention even at a high current density of 20 A g−1 in three electrode cell. A symmetric cell is fabricated using g-C3N4/MoS2 composite as both positive and negative electrodes to study the practical applicability of the electrode material. The cell exhibits an excellent performance with a maximum specific capacity of 198 C g−1 at a current density of 1 A g−1 and specific energy of 147 Wh kg−1 at a power density of 2691 W kg−1. This symmetric cell still delivers an energy density of 46 Wh kg−1 at a power density as high as 26.74 kW kg−1. Moreover, the cell exhibits extended cyclic stability with capacitive retention of 89% after 8000 cycles. This outstanding electrochemical performance suggests the future scope of g-C3N4/MoS2 nanocomposite as an efficient electrode material for energy storage devices.