Place sugar in a large bowl. Using a paring knife, slice off both ends of each orange. Following curve of fruit, cut away peel and white pith. Quarter lengthwise; cut crosswise into 1/2 -inch pieces. Add to bowl.
Cut off both ends of pineapple. Following curve of fruit, cut away peel. Quarter lengthwise; remove core. (Save half of pineapple for another use.) Cut remaining pineapple crosswise into 1/2 -inch pieces (about 3 cups). Add to bowl.
Cut kiwis in half crosswise. Use a spoon to remove flesh. Halve lengthwise, and cut into slices. Add to bowl; toss gently to combine. Serve in bowls.