Provided is a
physical quantity measuring device for reducing the influence of heat, other than the heat of a gas to be measured, on a measuring unit for measuring a
physical quantity of the gas to be measured. The
physical quantity measuring device according to the present invention includes a
chip package 40 and a casing 11. The
chip package 40 is molded from a polymeric resin, including first and second measuring units measuring first and second physical quantities of the gas to be measured, and a
signal processing unit being connected to the first and second measuring units, and
processing signals transmitted from the first and second measuring units, The casing 11 fixedly stores the
chip package 40, and includes first and second bypass passages 12 and 14 allowing the gas to be measured taken from a main passage 70, to flow in the first measuring unit. In the chip package 40, the
signal processing unit 44 is disposed between the first and second measuring units. In the casing 11, a cooling unit is formed for allowing the gas to be measured from the main passage 70 to flow between the first measuring unit and the second measuring unit, and cooling the
signal processing unit 44.