The present disclosure relates to an apparatus and method for diagnosing a learning ability. The apparatus for diagnosing learning ability includes a receiving unit configured to receive from a terminal chapter-related information or problem-related information which is desirably diagnosed by a learner, and a semantic information generator configured to generate, responsive to each piece of problem information included in the chapter-related information or problem-related information, semantic information with structural information of the problem information, the problem information having subject-specific problem information distinguished from the semantic information.