This thesis project had focused on studying of mixing ratio on properties of Agro stone caulking materials. In the experiment fixed ratio of filler of pumice and bagasse was used. Magnesia cement was used as binding materials; varying caulking were produced for different proportion of magnesium oxide and magnesium chloride solution (0.9:1, 0.95:1, 1:1, and 1.2:1, 1.32:1 kg per liter) with concentration of 28, 30, 33, 36 and 42 wt. % brine solution. The produced caulking material physical properties, mechanical properties and the free chloride ion were investigate. Physical properties such as water absorption of 14 and 26.4% minimum and maximum was obtained respectively. And also after curing for 14 days and 28 days the common mechanical properties namely tensile, compressive and flexural bending strength were determined with the help of computerized testing machines according to testing procedures, optimum results of the experiment was 3.8 MPa, 25.8MPa and 23.12MPa become the tensile, compressive and flexural bending strength test values respectively of the caulking material that uses ratio of 1:1 kg of MgO to liter of MgCl2. The free chloride ion that caused for corrosion was studied. The free chloride ion was reduced to 20% by adding 5%wt zeolite. Based on the above consideration the optimum ratio used for caulking was 1:1 with 36% of brine solution.