An apparatus and method for calculating a score of matching a sentence with a query pattern having a dependency structure. The apparatus includes: an input unit acquiring an analysis target sentence, a query pattern and an index value indexing how a linguistic unit in the sentence tends to modify another; and a score calculation unit calculating a matching score indexing the degree of matching of the sentence with the query pattern. The matching score is represented by a function having an index value with which a dependency relation included in the query pattern is associated. The score is calculated by attempting association between a substructure of the query pattern and a range in the sentence and by performing recursive calculation in the substructure and the range while storing partial calculation result of the function in a memory area for reuse.