In The Little Prince, author Antoine de Saint-Exupery gives no physical description of the narrator. What we know of the narrator is that he is an adult who works as a pilot. However, we are given a few details about the physical description of the little prince.
When the little prince makes his appearance in Chapter 2, the narrator describes him as being a "most extraordinary small person." What is also strange is that the prince appears in the middle of the Sahara Desert, where the narrator has crash-landed, yet does not appear to be afflicted with "fatigue or hunger or thirst or fear."
Yet, in Chapter 4, the narrator explains that detailed physical descriptions mean little to him because they say little about a person; therefore, he stops giving physical descriptions. He especially refuses to give the information the "grown-ups" would ask for such as how old the prince is and how much he weighs. Instead, the narrator only says that the prince was from a tiny planet, called an asteroid, that was barely bigger than the prince was and that the prince "had need of a sheep." The narrator also takes up drawing the little prince.
The reason why he relies on drawing the prince rather than giving physical descriptions of him is because the prince symbolizes the child self, which is connects to one's imagination and deep sensitivity. The narrator regrets that his child self has been oppressed by adult thinking and takes up drawing the prince to finally set his imagination and child self free.