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Light distributions of 12-years-old ´Fuji´ apple trees on M.26 rootstock in three orchards in Andong were measured and their relationships with fruit quality were evaluated. Tree shapes were a wide cylinder with some vigorously grown shoots spacing of 4×4 m in one orchard, a wide cone and a square cylinder with some moderately grown shoots and spacing of 4×3 m, respectively, in other two orchards. Even shaded in lower and inner parts of every canopy, light condition within the canopy of wide cone was the best, but the worst light condition was in the wide cylinder form tree. Light transmission values through the canopy of three different tree forms were decreased from the upper and the outer parts of in the canopy to the lower and to the inner parts the canopy, but there were no differences among quadrant positions. Light transmission values were declined rapidly as the leaf area index (LAI) increased, so transmission rates in the lower and inner parts of the tree canopies having higher LAI than 2.0 were lower than 30%. Leaves of the periphery parts of the canopy had higher specific leaf weight, stomatal conductance, and transpiration than those of the interior parts. It might mean that periphery leaves are more active in photosynthesis than interior leaves. The fruit quality such as fruit weight, color development and soluble solids contents improved as light penetration into tree canopies increased, but fruit firmness and acidity were not affected by different light penetration.
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