Lightweight self compacting concrete (LWSCC) is one of the latest innovations in concrete technology. This new type of concrete was developed to offer enhanced workability and durability due to its self-consolidation ability. Similar to normal self-consolidating concrete (SCC), these special fresh properties allow (LWSCC) to penetrate through formwork with complex geometry as well as through highly-congested reinforcing. Hence, (LWSCC) provides a better quality in the construction of the structural members with reduced labor. In addition, (LWSCC) also has a further impact on the construction cost by reducing the total dead load of the structural members up to 25%, and requiring less maintenance than a similar steel structure. (LWSCC) can achieve better strength and durability while offering excellent workability, and its mechanical properties are in general either competitive or superior to those in conventional lightweight concrete. This research was conducted to evaluate the roll of “Light Expand clay Aggregate (LECA)" in the manufacture of (LWSCC). By specific gravity factor method, six different mixes of (LWSCC) were cast and tested to find out the values of slump flow, G-ring, and compressive strength. Based on the results obtained, the best mix was selected to study the effect of the reinforcement ratio on the behavior of (LWSCC) one way slabs. The investigation examines also the behavior of the (LWSCC) one way slabs exposed to fire. The results demonstrated that the addition of (LECA) is possible to manufacture a structural (LWSCC) with low density, high self-consolidating, and with acceptance resistance to fire.