The possibility of using of rice husk ash (RHA) in the mortar was studied by performing experiments. The impact of RHA physical properties and chemical composition on dry-shrinkage of mortar is a potential problem, especially in the context of the increased use of new generation solutions and the development of new materials to ensure sustainability. In this study, the effects of RHA content, RHA particles size (fineness) and silica structure are evaluated. Comparisons are made over the full test period and at specific ages ranging from 3 days to 180 days. Incorporation of RHA provided lower dry shrinkage, where the amount of decrease in dry shrinkage increased with increase crystalline silica content and coarse particles size when compared to the control Ordinary Portland Cement (OPC) mixture, with finer RHA giving better improvement. Fine RHA exhibited the highest shrinkage value due to the effect of microfine particles which increases its shrinkage values considerably. Keywords: physical properties, chemical composition; fineness; dry shrinkage, crystalline silica