Hieroglyphs were deciphered by Champollion in 1822, since then the Egyptologists comprehend hieroglyphic writing fully, e.g. its system, grammar and construction of sentences. Hieroglyphs consist of semograms and phonograms, i.e. logograms, determinatives, phonograms and complements. This paper aims to research the usage of determinatives in the four inscriptions of king Merenptah, and discuss its development and purpose.