The present study aimed to compare the effect of different light curing modes (LED) of dual cured resin cement (cement IT universal C&B) on microleakage of fiber post(Fiberkleer taperd post).Materials and Methods: Forty intact human central incisor were collected .the teeth were decoronated 2m above the cement-enamel juncation using a low speed double sided diamond disk under constant water coolent. Arotary root canal preparation and obturation were performed using resin based sealer than mounted vertically in resin blocks using a special constructed device for this purpose.Results: The teeth were divided into two groups, first group (n=20) were prepared to receive fiber posts using total etch resin cement. Second group (n=20) were prepared to receive fiber posts using self etch resin cement. The results revealed that, pulse curing subgroup recorded the highest statistically non-significant (p>0.05) mean value (1.4± 0.45 score) followed by fast curing subgroup (1.3 ± 0.53 score) then halogen curing subgroup (1.2 ± 0. 3 score) meanwhile ramp curing subgroup recorded the lowest statistically non-significant (p>0.05) mean value (1.1 ± 0.3 score) as indicated by two way ANOVA followed by Tukey’s post-hoc tests.