A medical decision making support apparatus performs the inference processing of obtaining an inference result by performing inference processing associated with medical diagnosis based on a plurality of pieces of input medical information, and the calculation processing of calculating the degree of denial or affirmation of the inference result in association with each of a plurality of partial sets including each medical information extracted from the plurality of pieces of medical information as an element. The medical decision making support apparatus presents a user an inference result obtained by the inference processing and negative information indicating medical information included in a partial set, of the plurality of partial sets, for which the degree of denial is calculated by the calculation processing.