A disease development risk prediction system 10 includes: a data generation means 11 which generates combination data by combining at least two different types of receipt data using a combination key, wherein the receipt data includes an insured person number for an insured person which was converted using a predetermined method, a birth date or birth year and month which are both age-identifiable items, and gender, and the combination key combines the converted insured person number, age-identifiable items, and gender; and a model generation means 12 which uses the generated combination data to generate a prediction model predicting a risk of the insured person of developing a predetermined disease.