In this paper, at first the improvement susceptibility of calcareous sand is investigated using grouting method. The calcareous sand was obtained from Kish Island, located in Persian Gulf in south of Iran. The grouting process of sand was conducted using injection of a sodium silicate grout. It was observed that the maximum unconfined compressive strength, initial tangent modulus and failure strain of grouted samples are obtained in water/sodium silicate ratio of 0.5. Based on unconfined compressive test results, a model of micro pile was constructed, grouted and loaded axially. Results show that the sodium silicate grout increases the compression bearing capacity of micro pile model. The bearing capacity of grouted model of micro piles using a relatively moderate grout in loose sand is about 35 to 5.4 times of the un-grouted one located in loose and dense soil respectively. Also, the grouted model micro pile bearing increment is proportional to unconfined compressive strength of the grouted samples.