In this study, newly synthesized additive materials, organic-based magnesium compound (OBMAGC), organicbased manganese compound (OBMANC) and organic-based zinc compound (OBZC), were used as asphalt modifier. 50/70 penetration grade asphalt was separately modified with these additives at different concentrations ranging from 1% (w/w) to 10% (w/w). The effects of modification on the asphalt and hot mix asphalt (HMA) mixtures properties were detected through conventional tests (softening point test, ductility test, Marshall stability test, Nicholson stripping test, and indirect tension test) and Superpave methods (rotational viscosity, bending beam rheometer (BBR), and dynamic shear rheometer (DSR)). The proper concentrations for OBMAGC, OBMANC and OBZC to use in the modification of asphalt were determined as 3% (w/w) based on the rotational viscosity test results. Low temperature performance of the asphalt, as well as, stability and stripping resistance of the HMA mixtures were found to be improved by each of the additive. (C) 2012 Elsevier B.V. All rights reserved.