In this study, a novel inserted type of friction welding tool was proposed, where the circular rod was embedded in its central axis using the material same as the workpiece, so that it could effectively promote the friction heat quickly and enhance the welding quality. The welding tool was made of the high-speed steel, the workpiece with its embedded material 6061-T6 aluminum alloy. A vertical milling machine equipped with dynamometer, which could measure the power during the friction stir welding, was employed as the experimental apparatus. During the welding process, the K-type thermocouple was used simultaneously in measuring the welding temperature at the interface of joint. The operating conditions of welding were as followings: the welding speed of 800 rpm, the tool inclination of 1¢X and the clamping force 2kN, the tool with 12mm in diameter and 0.21mm in depth under the downward force about 2 kN. The experiment was conducted into two stages. The first stage was a spot welding to investigate the effect of the ratio of the diameter of embedded material (d) to the diameter of welding tool (D) on the temperature of the interface of joint, the thickness of plastic flow, and the failure load of weld. Experimental results revealed that the interface temperature, the plastic flow thickness, and the failure load of weld are directly proportional to d/D. In comparison with the welding tool without insert (d/D = 0), the maximum interface temperature increased about 1.12 times at d/D = 0.83, the plastic flow thickness increased about 1.52 times, and the failure load of weld increased about 1.45 times. In the second stage, the feeding process was included to investigate the influence of the diameter and the thickness of embedded material on the interface temperature, the plastic flow thickness, and the failure load of weld. Experimental results revealed that the plastic flow thickness was less than 2 mm when the thickness of embedded material was less than 3 mm. However, when the thickness of embedded material was larger than 5 mm, the plastic flow thickness could achieve to 3 mm. Hence, the thickness of embedded material should be larger than 5mm. Moreover, the effect of the diameter of embedded material on the interface temperature and the plastic flow thickness using the feeding process was almost the same as the spot welding. However, in comparison with the welding tool without insert, the failure load of weld increased about two times.