The purpose of this study is to examine the complement clause appeared for the time being in the past school grammar textbooks and also examine the complement and complement phrase in the past school grammar textbooks. The complements were presented as the main constituent of the basic sentence patterns or the essential component of incomplete predicate combining with complement case marker in the past school grammar textbooks. The establishment of complement, complement phrase, complement clause were based on the argument of incomplete predicate, ‘되다, 아니다, 같다’. While the embedded clauses are based on the formal markers in the present grammar, the complement clauses were based on the sentence constituents in the past school grammar textbooks. The complement clause had the subject-predicate relation and co-occurred with incomplete predicate. Therefore the complement clause of the past school grammar textbooks, combining with nominal, quotative markers have segmented into noun clause, quotative clause in the present grammar which is based on the formal marker.