Permeable geotextile tubes are usually made by sewing geotextile sheets together and then filling with clay slurry or sand. However, the tensile strength of a seamed woven geotextile material is usually only half of that of the seamless geotextile sheet. A new seam method has been proposed to improve the tensile strength of the seamed woven geotextile material. The main idea of the method is to reinforce the geotextile on the area of the pin-hole side which was the weakest part in the traditional seaming methods. The test results show that after the seam had been reinforced, the percentage ratio of its tensile strength to the strength of seamless geotextile sheet was improved by more than 75%.