A wealth of literature shows that the giant panda (Ailuropoda melanoleuca) has well-developed olfactory and auditory systems but poor eyesight. Although there are some studies of the visual ability and colour vision in the giant panda, little is known specifically about its eyesight. To quantify the giant panda’s visual acuity, we observed and recorded the behavioural responses of 8 captive giant pandas (M: F=4:4) to moving pieces of paper with horizontal black and white stripes of various width. We found that giant pandas are able to distinguish white stripes from black stripes at a distance of 50 cm when both were approximately 0.46 mm wide. This result provides additional behavioural support for anatomical studies of the retinal structure of the giant panda and will aid further studies of communication and cognition in this treasured animal species.