To provide a differential pressure measuring apparatus that can easily and inexpensively confirm that connecting piping is clogged.

In the differential pressure measuring apparatus, measurement fluid is introduced to a differential pressure measuring apparatus body via a connecting pipe. The differential pressure measuring apparatus comprises: a heating/cooling means that is provided in the connecting pipe or the differential pressure measuring apparatus body, heats or cools the measuring fluid, and expands or contracts the measurement fluid; and a detection means for comparing the pattern of change in output that occurs in the action of the heating/cooling means with the normal state of the differential pressure measuring apparatus to detect the clogging of the differential pressure measuring apparatus.