A pressure sensor configured to prevent tearing or cracking of an insulating film for insulating between a stem and a detection circuit from occurring. A stem having a planar outer bottom surface, an outer side surface intersecting the outer bottom surface, and a pressure receiving inner surface that is the opposite surface to the outer bottom surface and receives pressure from a fluid to be measured; and a detection circuit provided to the outer bottom surface with an insulating film interposed therebetween. The stem has a foot part that: is formed to surround the outer bottom surface; consists of a surface which, when observed parallel to the outer bottom surface, faces a direction different from the direction of the outer bottom surface and the outer side surface; and connects between the outer bottom surface and the outer side surface. The insulating film covers a portion of the foot part.