This paper is the best one in the DataMining session in the ICPET 2018. Paper about: Graph-based Technique for Extracting Keyphrases in a single document (GTEK) is introduced. GTEK is based on the graph-based representation of text. GTEK motivated by: A phrase may be important if it appears in the most important sentences in the document. The Most important KP must cover all sub-topics of document. GTEK groups the sentences into graph-model clusters. Then ranks them using TextRank algorithm. Finally, the most frequent phrases in the high ranked sentences are selected as document keyphrases. Experimental results show that GTEK extracts the most keyphrases of two datasets.