The purpose of the present study was to evaluate the early marginal microleakage in 20 Class II MOD restorations made in association with conventional and sandwich technique. Human extracted third molars were used in the study. Multi-incremental technique was used in all restorations. After finishing, the teeth were stored in dye solution for 12 hours, transversally sectioned at three levels and evaluated under optical stereomicroscope. Cervical sections showed the highest marginal leakage. Sandwich technique in association with glass-ionomer cements have showed a significant lower early microleakage with respect to the conventional technique.