Objective To assess the change of the motion perception of cones in patients with AMD. Methods Motion perceptions of B、G and R cones of 20 eyes with dry type AMD were isolated by blue,green and red random dots stimulus displayed on the yellow,purple and blue-green background respectively,and keeping equiluminance between stimulus and background. Results The detecting displacement threshold and identifying threshold of motion perception from B,G and R cones were all damaged in eyes with dry type AMD compared with the normal group. Conclusion The abnormal changes of motion perception may reveal preclinical damage of visual function damage in dry type AMD. (Chin J Ocul Fundus Dis, 1999, 15: 219-221)