Physical Quantity Detection Device

To obtain a physical quantity detection device capable of reducing an intake amount of air accompanied by foreign matter. A physical quantity detection device () of the invention includes a housing arranged in a main passage through which a measurement target gas () flows. The housing is provided with a second sub-passage (B) that takes in a part of the measurement target gas () flowing in the main passage, a circuit chamber () that accommodates a pressure sensor () that detects a pressure of the measurement target gas (), and a pressure introduction passage () having one end opened in the middle of the second sub-passage (B) and the other end opened in the circuit chamber () and capable of introducing the pressure of the measurement target gas () from the second sub-passage (B) into the circuit chamber (). In the pressure introduction passage (), an introduction port () is arranged at a position offset outward from a side wall surface () of the second sub-passage (B).