Provided is a pressure measuring device including a first electric resistor that is exposed to gas; a second electric resistor that is exposed to gas and has the same structure as that of the first electric resistor; a first measuring unit that measures a first voltage drop generated across the first electric resistor; a second measuring unit that measures a second voltage drop generated across the second electric resistor; a third measuring unit that measures a third voltage drop generated across the first electric resistor; a calculating unit that calculates a correction value that corrects the third voltage drop, based on a difference between the first voltage drop and the second voltage drop; and an output unit that corrects the third voltage drop using the calculated correction value and outputs a pressure value according to the third voltage value after the correction.