An attitude measuring method for excavator’s manipulator based on vision measurement was proposed. Using the industrial camera to grab the perspective images of the manipulator, a saddle point detection was adopted to detect the manmade targets which was fixed on every arm of the excavator. Then the fixed geometric dimensioning between two targets was used as a constraint condition to select the saddle point in targets, and the attitude angle of the corresponding arm can be derived from the saddle point coordinates. The image detection area was reduced through anticipation of target movement and the algorithm processing speed was improved. Experiment results showed that compared with the original displacement sensor system installed on the excavator, the measured deviations of dynamic attitude angle for boom and arm were less than 1 degree and 2 degrees, respectively. The average processing time of this method for each manipulator movement frame was within 100ms. And the feasibility of this method for measuring excavator manipulator’s attitude was verified.