In this research, the combustion performance of a novel, composite hybrid rocket fuel grain composed of Acrylonitrile Butadiene Styrene (ABS) and Paraffin was investigated to understand the effects of incorporation of a novel nanomaterial: gel-like carbon dots (CDs), into the paraffin component. ABS fuel grains with straight ports were 3D printed and used as molds into which base and 1 wt% CD-loaded paraffin materials were casted separately. For control, pure ABS fuel grains were also printed. All fuel grains were exposed to ballistic tests using the lab-scale test setup where gaseous oxygen (GOX) was employed as oxidizer. Test results exhibited that ABS/CD-loaded paraffin fuel grains manifested a maximum combustion efficiency and regression rate of 88% and 1.29 mm/s, which marked enhancements of about 8.5% and 11% compared to ABS/pure paraffin fuel grains, respectively. Despite the compromise in the mechanical properties, the enhancement in combustion characteristics of CD-loaded fuel grains was attributed to lower viscosity, higher particle entrainment, specific surface area and catalytic activity