Nowadays, due to Growth of construction industry the Demand of cement becomes increasing in every year. The production of cement also environmentally unfriendly due to release of C02, energy consumption and escalated by the price. To diminish problems related to cement production there should be used alternative materials. So, the objective of this investigation is to evaluate the possibility of one of silica oxide rich silica sand powder as Pozzolanas material in order to reduce the release of C02 and high cost of cement resulted from the manufacturing of cement. The effect of silica sand powder on consistency, setting time, soundness, workability, compressive strength, ultrasonic pulse velocity, water absorption, sulfate resistance, porosity was investigated. In addition to that, Fourier Transform Infrared, Thermogravimetric Analysis, and Differential Thermal Analysis were done to evaluate the micro-structure of mortar. In this study, Mortars specimens were did tests at the ages of 3, 7, 28 and 56days by containing different contents of Silica sand power (0%, 5%, 10%, 15%, 20% and 25%) of replacing ordinary Portland cement. The Mineralogy result indicated that Silica sand contain majority of its oxide is Silica oxide and its meets ASTM C 618 standard. The introduction silica sand powder in cement paste increase the water demand, Fineness, setting time, and reduced cement expansion. With increasing of silica sand powder workability of mortar decreased. The incorporation of Silica Sand Powder result on 3 rd , 7th, 28th and 56 th days shows that up to 10% Silica Sand Powder addition improve compressive strength than reference mix. After 10% replacement compressive strength decrease as level of replacement increase. The result indicated that the optimum level of replacement 10% SSP reduce porosity of mortars, water absorption, improve Ultra Sonic Pulse Velocity, good sulfate resistance, improve morphology of mortar relative to Control mix. Keywords: silica sand powder, durability, Micro structure properties, Fresh properties, Mortar