The invention belongs to the field of mode recognition, 
computer vision and 
image processing, particularly relates to an 
iris image segmentation and positioning method, 
system and device based on deeplearning, and aims to solve the problem of low 
iris recognition precision in a non-controllable scene. The method comprises the steps that a to-be-processed 
iris image is acquired; four mapping images are generated by adopting a multi-task neural 
network model, wherein the four mapping images respectively correspond to a 
pupil center, an iris inner boundary, an iris outer boundary and an iris segmentation 
mask; the iris segmentation 
mask mapping graph is processed by adopting threshold segmentation to complete iris segmentation; the 
pupil center position is predicted according to the geometrical relationship between the 
pupil center and the iris 
mask; the mapping graph is de-noised and calculated by utilizing a geometrical relationship among the pupil, the iris and the 
sclera to obtain iris inner and outer circle parameters and finish iris positioning. According to the method, the 
iris image acquired in the non-controllable environment can be effectively segmented and positioned, a good foundation is laid for subsequent normalization and recognition, and the 
iris recognition precision in the non-controllable environment is improved.