Carbon dots (CD)-based light-emitting diodes (LEDs) with low cost, easy acquisition, and environmental friendliness are an emerging display technology worth further exploration. However, it is still a challenge to prepare CD-based LEDs with high performance and spectral modulation. In this study, green-emitting CDs (G-CDs) were prepared into LEDs by the traditional solution method. These G-CD-based LEDs reach maximum brightness and external quantum efficiency of 400 cd/m2 and 0.02%, respectively.