Abstract: For that rotating arc sensor welding torch can be convenient for welding operations in narrow space, research on welding torch spatial attitude analysis and identification is essential. The mathematical models of welding torch height is established, and then welding torch height variation and its effects on weld seam deviation extraction accuracy are analyzed under the different welding torch tracking angles, welding torch working angles, welding torch traveling angles, weld seam deviations and groove angles. Simulation results show that welding torch working angle influences the greatest on weld seam deviation identification accuracy, the others are within a reasonable range. However, the weld seam deviation recognition accuracy is not stable with variation from welding torch spatial attitude. The above provides a theoretical basis for decoupling reasonably and indentifying precise exactly.