An information processing apparatus which anonymizes data composed of records including one or more items through statistical processing, includes a memory and a processor to execute classifying respective records constituting the data into one or more sets based on masking target items indicating items to be masked among the items, a dictionary which expresses categories of item values in a tree structure for each of the masking target items, a selected hierarchy level indicating a hierarchy level selected in the tree structure for each of the masking target items, and the number of records included in the data, and calculating the number of records N of each set and a ratio of records belonging to a set including N records, and dividing the data into one or more pieces of data in a case where the ratio of the records belonging to the set including N records satisfies a predetermined condition.