PURPOSE: To provide a composition for preventing oxidation and carburizing, capable of preventing oxidation and carburizing simultaneously, by forming a coated film layer having a monolayer structure.

CONSTITUTION: A composition for preventing the oxidation and carburizing of a steel material, which contains, by weight, 5-90% flux component having ≤1300°C softening point or melting point, 5-90% Sin, 5-60% Cr2O3 and 0-75% refractory filler having ≥1300°C melting point, is prepared. This composition is applied to the surface of a steel material before heat treatment.