The breeding success of the Golden Eagles Aquila chrysaetos living on the Kitakami Plateau has been declining rapidly, as in other regions of Japan. The relationship between breeding success and the composition of the vegetation in areas within a 6.4 km radius of their nests was analyzed using data from surveys conducted in 1979-1988 and 1995-2001. The relationships between breeding success, nest overhang, weather conditions, and direct human stresses were also analyzed. Breeding success fell from 67% in 1979-1988 to 27% in 1995-2001. Meanwhile, the area of young forestry plantations of less than 11years old (and so suitable for hunting) declined by 77%, and shrubs and seminatural meadows were also reduced, by 43%. Results from a regression analysis showed that breeding success was positively correlated with the area of mature, deciduous broadleaved forests older than 100 years, young plantations, and shrub and semi-natural meadows within a 6.4 km radius. Breeding success was negatively correlated with the inferior condition of nests (the extent of overhang) and the altitude of nests. Breeding success was not affected by either temperature or precipitation during the nesting and breeding periods. The proportion of breeding failures resulting from direct human disturbance was just 6% in 1979-1988, but 19% in 1995-2001. A remarkable reduction in breeding success between these periods was partly accounted for by the reduction in suitable hunting habitats. The maintenance, creation or regeneration of suitable hunting environments, such as mature, deciduous broad-leaved forests, young plantations, and shrub and semi-natural meadows, is necessary to improve the breeding success rate of the Golden Eagle on the Kitakami Plateau