The Egyptian roads suffer from a lack unevenness of the surface after a short period of construction, due to the creep of the asphalt layer, especially at the sharp horizontal curves and in heavy truck lanes, and this depends largely on the mechanical properties of the asphalt layers Therefore, in order to extend their service life, scientists and engineers are constantly trying to improve the mechanical properties of the asphaltic mixtures. One common method of improving the performance of asphaltic mixtures is using of different types of chemical additives. The objective of this research is to study the effect of using chemical additives on the ability of the HMA to resist the deformations such as creep. Three different chemical additives were used. The chemical additives were Addicrete PVS, Adibond 65 and Silica Gel, that were added with different percentages such as 0,5, 10, 15 and 20 % (by the weight of optimum asphalt content). Creep test was performed on these mixtures with its different contents and comparing the test results of these additives with the original mix in order to study the extent in improvement the properties of the different mixtures with these additives. It was found that using of Addicrete PVS and Silica gel at 10% content increased the value of creep stiffness while decreased the creep value in comparing with the original one. Also, using of Adibond 65 with 15% content achieved the same trend and the best material which given the best results was Silica Gel that reduced the creep value by 35.7% while increased the creep stiffness by 59.5%.