A pipe diagnosis apparatus 10 includes a time-series data acquisition unit 11 that acquires time-series data on pressure of a fluid in piping equipment to be diagnosed, a pressure change measurement unit 12 that measures the number of pressure changes in the fluid from the time-series data on the pressure of the fluid, and a failure risk estimation unit 13 that estimates a failure risk of the piping equipment based on the measured number of pressure changes and a strength of a pipe included in the piping equipment.