The present invention relates to a triazine type monomer, and more particularly, to a 1,3,5-triazine type monomer characterized by having at least one amine group and at least two sulfur atoms, which can be used in manufacturing transparent optical resins having excellent refractive index, surface hardness and absorbance as well as an improved workability and the ability to control a wide range of refractive index according to the change in composition by the monomer itself at room temperature or by polymerizing the monomer with a comonomer in the presence of an organic solvent or an initiator.