The present invention provides a pressure detector including: a case that can be connected to a flow path of a liquid； and a membrane member that is attached inside the case, that defines a liquid phase part, which can be filled with the liquid in the flow path, and a gas phase part, which can be filled with gas, and that can be displaced in accordance with the pressure of the liquid filling the liquid phase part, the pressure detector detecting the pressure of the liquid in the flow path by detecting the pressure of the gas phase part. The pressure detector is characterized by having a flow-in port having a connecting part that can be connected to the flow path of the liquid and having a flow path part that allows the liquid to flow in from a flow-in hole in the liquid phase part, and a flow-out port having a connecting part that can be connected to the flow path of the liquid and having a flow path part that allows the liquid having flowed in the liquid phase part to flow out from a flow-out hole. The pressure detector is also characterized in that at least one of the flow path part of the flow-in port and the flow path part of the flow-out port is configured such that the liquid flow-in direction or the liquid flow-out direction thereof is inclined with respect to a surface to which the membrane member is attached.La présente invention concerne un détecteur de pression comprenant : un boîtier qui peut être relié à un trajet d'écoulement d'un liquide； et un élément de membrane qui est fixé à l'intérieur du boîtier, qui définit une partie de phase liquide, qui peut être remplie avec le liquide dans le trajet d'écoulement, et une partie de phase gazeuse, qui peut être remplie de gaz, et qui peut être déplacé en fonction de la pression du liquide remplissant la partie de phase liquide, le détecteur de pression détectant la pression du liquide dans le trajet d'écoulement par détection de la pression de la partie de phase gazeuse. Le détecteur de pression est caractéri
