The chemical grouting methods have been widely used as liquefaction mitigation methods. However, the injection loss due to the leak of chemical liquid from the drilling hole and the injection inhibition due to the borehole wall failure have been often observed. In this study, we developed a new chemical grouting method to overcome these problems. A developed chemical grouting method has two unique technical features. One is the packer which is made up of cloth and rubber. The other is a special sealing material which protects the borehole wall during drilling and is fluidized during the chemical injection. From the trial in-situ injection tests results, it was found that 1) the leak of chemical liquid from the drilling hole has not been observed, and 2) a wide range of chemical grouting has been achieved by about 30% of the injection pressure compared to the conventional Double-Pipe Double-Packer method.