The 3D printing of pre-ceramic polymers that can be pyrolyzed into functional ceramics has recently become a focus for advanced ceramic applications requiring complex geometries. In this work, a new methodology for 3D printing SiCNO ceramic materials derived from a novel pre-ceramic photopolymer feedstock utilizing a thiol-ene reaction is introduced. The printed parts are pyrolyzed to amorphous SiCNO and the physical and mechanical properties of the final ceramic are measured. Pyrolysis of the pre-ceramic produced a SiCNO ceramic with 41% ceramic yield and shrinkage of 24% with a hardness measured at 6.6 GPa ± 0.3 GPa.