Vanadium nitride is a negative material with extensive application prospects in energy storage fields; however, its stability under long cycles and high current density is still an urgent problem to be solved. The preparation of nanoscale vanadium nitride structures with carbon protection has become mainstream to solve these problems. Thus, designing and constructing a more optimized vanadium nitride and carbon composite structure is the key to improving the performance of electrodes. Herein, the carbon sheet mosaiced with the vanadium nitride quantum dots is fabricated by self-assembly of V3+ and the deprotonated poly (paraphenylene terephthalamide) chains. As supercapacitors negative materials, the vanadium nitride quantum dots@carbon exhibits high specific capacitance reaching 532 F g−1 at the current density of 0.5 A g−1 and capacity retentions of 67% after 5, 000 cycles. The good electrochemical performance is attributed to the continuous fast electron transmission path and amounts of the electrochemical reaction site of the mosaic structure. This study offers a facile and novel method for vanadium nitride-based electrode challenges.