The purpose of this study is to determine the difference of of sealing ability in the root canal between glass ionomer and epoxy resin, irrigated and nonirrigated with EDTA 17% The research was klinis laboratory using 16 permanen mandibular premolars which have been extracted and grouped into 4. These 4 groups were group A (glass ionomer + EDTA 17%), group B AH Plus + EDTA 17%, group C (glass ionomer + aquabides), group D (AH Plus + aquabides) that prepared and obturated with single cone technique then covered with nail polish. All groups were incubated in 37oC during 24 hours and immersed using black ink foodcoloring during 7 days. The samples were observed and calculated for black ink penetration using stereo microscope in millimeter unit. The result was analyzed by Kruskall Wallis test and Post Hoc Mann Whitney U T est. The result from this study shows there is diference of sealing ability in root canal wall using glass ionomer type 1 and AH Plus that irrigated or non-irrigated with EDTA 17% (p<0,05). The good sealing in root canal wall is AH Plus that irrigated EDTA 17%.