Novel as a literary work can be analyzed by using semiotic analysis. This article aims to analyze the meaning of index found in characterizations in the novel "The Man in the Iron Mask" by Alexandre Dumas. This article involved the descriptive qualitative method. The results revealed that there are many causal relations between the index and the characterization of the characters found in that novel. It contained 24 characterizations from eight major and five minor characters that had been representative of this article. From this article, it is obtained more information about the identified characterizations found in the novel and its index analysis that showed its causalities relation between the sign and the object (index and characterization) in a more comprehensive meaning. Since semiotics is the study of signs and novel is a literary work, it is recommended to English literature lecturers and students to enrich knowledge of analyzing literary works through semiotic analysis.