The strength of the O-H···O hydrogen bridge in acetylacetone (AA) and acetylacetone derivatives is depending on the nature and size of the substitute groups and on the substitution position. We investigated the effect of electron-pull and electron-donor substitute on the formation of intramolecular hydrogen bonding at 3-substituted acetylacetone derivatives such as nitroacetylacetone (NAA) and methylacetylacetone (MAA). In this research NAA and MAA structures were fully optimized with B3LYP/6-31G*, 6-31G** and 6-311G**. From the electronic data we found that intramolecular hydrogen bonding in NAA is stronger than MAA.