To assess the effect of post-space treatment with chelating agents on the push-out bond-strength of a glass fiber post-system. Fortyeight human teeth were decoronated. The roots were prepared to size 40 and obturated. The post-spaces were prepared with PeesoReamer drills. The post-spaces were irrigated with (i) NaOCl and EDTA with chlorhexidine (QMix), (ii) NaOCl and EDTA, (iii) NaOCl and Citric acid, (iv) NaOCl and saline as a control group. i-TFC glass fiber posts were then luted with i-TFC bond system. The samples were horizontally sectioned. The displacement resistance was measured. Push-out bond-strength (MPa) was calculated. Data were analyzed. NaOCl/QMix group showed highest values to dentine whereas NaOCl/Citric acid group showed lowest values. i-TFC post-system demonstrated equal bond strength values when post-space treated with either NaOCl/EDTA or NaOCl/Saline. It can be concluded that post-space could be treated with NaOCl and QMix in order to increase adhesion of i-TFC post-system to rootdentine.