The present study is concerned with the effects of familiar-size cue on the judgments of size and distance for the children of an elementary school. Thirty-two 1st-, 3rd-, and 6th-grade children served as subjects. The experiment consisted of repeating alternations of the two steps: A judgmental step in which the subject judged the size and distance of transparencies of familiar objects, and an informational step in which the subject was acquainted visually or haptically with the real sizes of a toy car and a toy dog from which the transparencies were made. The results revealed that: (1) The younger children tended to make judgments resulted from the normal sizes of the familar objects that they encounter in their daily life, while the older children based their judgments on the size information given by looking on or touching the real toys. (2) Visual size information was superior to haptic size information both in size and distance judgments. (3) Familiar-size cue may be effective in relative rather than absolute size and distance judgments.