Charactonym is proper name that is used to name the characters in literary work Characteristics of literary characters in a story leads to their identity role and personality trait. Related to this case, this research is aimed to discover charactonym contribution to the character information based on the first name meaning regarding with the name function. This research uses descriptive qualitative method. The data used in this research are collected by document analysis method. This research applies the content analysis to analyze the data. The result of data analysis discovers 39 data analyzed in this research. The 17 names function as individualization, 10 names as identification, and 12 names as establishment. It can be concluded that J.K. Rowling‟s mastering of some languages, French, German, Classics with Greek and Roman studies influence her unique character‟s names. She considers the name for her characters to convey a message to the reader. J.K. Rowling tends to give the key of what her character is like and how her characters treat themselves and others. There are 56% names that reveal the character information, and 44% names are a label so far. The name function depends on what important role of each character has in the story.