aim of the study: to evaluate dentin bond strength, sealing ability, adaptation and penetration into dentinal tubules of epoxy resin based sealer (MM-Seal) and MTA based sealer (MTA Fillapex).   methodology: Forty extracted human central permanent incisors were selected and decoronated. The canals were instrumented using crown down technique by Revo-S rotary system and obturated using single cone technique. The teeth were divided into two groups (n=20) according to sealer that used in obturation (MM-Seal or MTA Fillapex). For all samples, the coronal three millimeters were used for bond strength test. The remaining apical portions of each group were further divided to be used for dye penetration and SEM evaluation. The obtained data was analyzed using the One Way ANOVA and failure modes were classified as adhesive, cohesive or mixed.   Results: Push-out bond strength test showed that, MM-Seal showed significantly higher values than that of MTA Fillapex while MTA Fillapex showed significantly higher values than MM seal regarding dye penetration test. There were no statistically significant differences between the two filling materials regarding the adaptation and the penetration into dentinal tubules. Conclusion: MM-Seal root canal sealer performed better than MTA Fillapex in respect of bond strength to dentin of the canal wall, adaptation and penetration into dentinal tubules and lower dye penetration than MTA Fillapex root canal sealer