Post retention in root canal is an important factor on the clinical success of restorations in endodontically treated teeth. AIM: To evaluate the effect of luting agent, fibreglass post design and lengths on the bond strength of posts. MATERIALS AND METHOD: One hundred eighty single-rooted teeth were root filled and prepared to receive either a parallel-sided and serrated fibreglass post or a tapered and smooth fibreglass post (n=90). The posts were cemented with the following resin cements: dual-cured resin cement (RelyX ARC), self-adhesive resin cement (RelyX Unicem) and a self-cured resin cement (RelyX ARC Luting) (n=30). The posts were luting in different depths: 5.0 mm; 7.5 mm; 10.0 mm (n=10). The posts were submitted to a traction test at a speed of 0.5 mm/min and the bond strength values (MPa) were submitted to anova in a split-plot arrangement and Tukey’s test ( α < 0.05). RESULTS: The analyses of bond strenght values revealed that post length (depths of luting), resin cement and post design was statistically significant ( α < 0.05). The highest values of retention were observed in the smooth posts. No difference of retention values was observed in the posts cemented into 5 or 7.5 mm. The highest values were obtained cementation depth of 10 mm. The RelyX ARC and RelyX Unicem showed the highest values of retention. CONCLUSION: Greater depths of cementing provide greater retention. Dual-cured resin cement and self-adhesives had the highest retention values especially when the post format used is smooth and tapered.