A semiconductor differential pressure sensor element is such that as strain sensitive elements are disposed only inside a diaphragm, and strain relaxation grooves are provided along the diaphragm, it is difficult for thermal stress caused by expansion or contraction of a case to propagate to the strain sensitive elements, thus suppressing characteristic fluctuations resulting from a change in external temperature. Also, as a configuration is such that a sacrificial column is provided inside a depressed portion, and that the diaphragm is held by the sacrificial column in a diaphragm formation step which thins a second semiconductor substrate and a functional element formation step which repeatedly implements a cleaning step, breakage of the diaphragm can be prevented, thus achieving a significant improvement in yield.