PROBLEM TO BE SOLVED: To obtain a method and an apparatus for surface defect determination for a continuously cast slab, enabling a high quality slab to be produced.SOLUTION: The method for surface defect determination for a continuously cast slab related to the present invention comprises: a cast mold copper plate temperature acquisition step of acquiring a cast mold copper plate temperature measured by thermocouples (temperature measuring elements) 5; a main component analysis step of calculating a main component score by carrying out the main component analysis on the basis of the acquired cast mold copper plate temperature; and a main component score determination step of determining presence or absence of defects in the surface of a cast metal on the basis of the calculated main component score. The thermocouples 5 are embedded in a cast mold long side and are arranged in such a manner that: in the casting direction, a position of the uppermost stage temperature measuring element is within 250 mm from a
