Search information in the form of a document or a text known as Information Retrieval (IR) is a separation process documents that are relevant from a set of documents available. The increasing number of thesis documents are available allowing the similarity theme or topic of discussion was appointed as the thesis title. Stemming is a process that converts all the words in a text document into "rootword" or principal said. Rootwords are stored as an index. Each index which stored to be used as a comparison to the new document. By using the concept of Similarity, the index comparisons of old documents with new index documents can be obtained degree of similarity to certify the appropriateness of the thesis title.