Most kinds of welding positioners at present are aim at welding position-change of one workment. Therefore,two or more positioners are required to coordinate and perform the displacement operation if welding and position-change are related to more than one workments. And this leads to low welding efficiency and high cost. In order to solve this problem,this paper designed and analyzed a new type of welding positioner,which can realize rotational position-change,assembling and welding,independent and synchronous positi on-chan ge of two workments by coordination among two abreast welding clamping mechanisms,revolute joint and driving mechanism. SolidWorks analysis results show that its structure meets the requirements. And it is proved by tests that it can effectively improve production efficiency and productivity.