In the article，the composition and work theory of laser deception angle measurement system are introduced.By quoting the evaluation method of expanded uncertainty，the measurement uncertainty for laser deception angle is analyzed.The main factors of the measurement uncertainty for laser deception angle are confirmed，including demarcate standard deviation of laser deception angle measurement system，standard deviation of laser tracking，standard deviation of television tracking and standard deviation of television angulation.The methods which can decrease the uncertainty of measurement in the process of using the laser deception angle measurement system are presented.