On the basis of the original iris location method based on the structure feature, an improved method is proposed. To the iris’ outer boundary, we use the feature of the iris’ structure and mathematical means to verify whether the iris outer boundary points are correct, and calculate the correct ones if necessary. Because of the disturbances of the eyelid and the eyelashes, the original iris location method based on the structure couldn’t locate the iris accurately, but the proposed method could effectively solve the problem. 1200 iris images (640×480 in size) comprising an iris image database are located in the experiment. The location accuracy of proposed algorithm reaches 99.08%, average time of location is only 0.8 s. The availability of proposed method is proved in the experiment.