Lightweight concrete has been widely used in different structural applications and its consumption grows every year on a global basis. The reason for this is that using lightweight concrete has many advantages. These include: a reduction in the dead load of the building, which minimizes the dimensions of structural members; the production of lighter and smaller pre-cast elements with inexpensive casting, handling and transportation operations; the provision of more space due to the reduction in size of the structural members; a reduction in the risk of earthquake damage; and increased thermal insulation and fire resistance. The main objective of this dissertation is to study the properties of cellular lightweight concrete blocks. Lightweight cellular concrete blocks are casted with 65% of Fly ash and 35% of cement with foam content 1.5% of total weight and to increase its strength sand and quarry dust is added in its composition which replaces fly ash up to 30% at an interval of 5%.