To provide a Kana mixture notation extracting system which mechanically extracts notation variability of terms.

This Kana mixture notation extracting device 10 decomposes a character string of the term registered in a dictionary and stores them with readings in Kana applying for each decomposed character. All the characters and readings in Kana are combined to generate notation candidates, and searching is performed using the notation candidates as search keywords. Based on the search results, the notation variability is extracted from the notation candidates, and the terms and the notation variability are associated and stored.