In this study, on microstructure and mechanical properties of Al-Si-Mg alloy was investigated effects of ceramic foam filters having different density of cell. Ceramic foam filters is used to minimizing bifilm, inclusion, sand wash away from of the mould wall, gas or shrinkage porosity such as casting defects. As a result of the tensile test results were evaluated with Weibull distribution and the quality index. Mechanical properties and castability were examined by ceramic foam filters using in Al-Si-Mg alloy. Experimental studies were used on horizontal runner a ceramic foam filter having different density of cell (20 and 30 ppi). According to Tensile test results, due to the increased density of ceramic foam filter cell gap could be controlled flow behaviour of the liquid metal in the running system. Improving mechanical properties of Al-Si-Mg alloy has been demonstrated by increasing Weibull modulus and quality index. In addition to increasing the amount of cell gap in ceramic foam filter, quality index is also increasing. Tensile fracture surfaces of samples was investigated Scanning Electron Microscope (SEM), to fracture occurs secondary intermetallic phases, inclusion and bifilm defect concentration regions.