PURPOSE: A method for fabricating carbon fiber with improved opening property is provided to remarkably improve opening property of final carbon fiber by treating the carbon fiber with sizing agent. CONSTITUTION: A method for fabricating carbon fiber with excellent opening property comprises: a step of preparing polyacrylonitrile(PAN)-based precursor spinning solution containing 8-15 wt% of PAN polymers; a step of spinning the PAN-based precursor spinning solution by a dry spinning method; a step of performing precipitating bath and heat stretching in a solidifying solution containing ZnCl_2 to prepare a precursor carbon fiber for 20-40 seconds; a step of performing flame retardance treatment and carbonization; and a step of treating the carbon fiber with a sizing solution containing two or more compounds.
