1. An information recommendation method which uses a server including a processing unit and a storage unit, reflects a response of a user receiving information related to an item in a selection criterion of an item to be recommended next time, and recommends another item, the information recommendation method comprising operations wherein: the processing unit collects information to which the user reacts and information to which the user does not react, compares the degree of similarity between an unrecommended item and an interest item to which the user reacts with the degree of similarity between the unrecommended item and a no interest item to which the user does not react, and determines the next recommended item to the user by using the comparison result; the processing unit estimates a boundary of interest and no interest, which is a boundary between the interest items and the no interest items, in all items to be recommended, by expanding unrecommended items similar to the interest item and the no interest item respectively from the interest item and the no interest item; and the processing unit determines the unrecommended item on the boundary of interest and no interest or near the boundary of interest and no interest or the interest item determined by the boundary of interest and no interest, as the next recommended item.