With the development of use of lasers in dentistry, and submitted suitable wavelengths for safe cutting of the dental tissue, laser was suggested as an important alternative preparation method, that because of its advantages such as (the anesthesia is not often needed, preservation of sound dental tissue and the lack of noise which comes along with high speed handpiece. The of this study was to evaluate the bonding strength of a posterior composite restorations when two different types of equipment methods were used for preparation of dentin (Erbium-doped yttrium aluminum garnet laser (Er: YAG) and diamond burs. Results showed no significant differences between the levels of bond strengths in bur-cuted dentin and lased dentin, as well as no significant effects due to the difference of restorative material and the bonding system used.