A measurement device for measuring an airflow volume and a ventilation resistance of a wind-blowing apparatus, comprising: a housing that includes an air duct with an air inlet and an air outlet , the air inlet being configured to take in air, the air outlet being configured to send out the taken air; a straightening grid configured to straighten the air taken from the air inlet , an opening member installed inside the air duct , the opening member including an opening allowing the air taken from the air inlet to pass therethrough; a first differential pressure sensor configured to measure a first differential pressure between air pressure from the air inlet to straightening grid before the air passes through the straightening grid and atmospheric pressure of the outside air obtained through an outside air-port ; a second differential pressure sensor configured to measure a second differential pressure between air pressure from the straightening grid to the opening member before the air passes through the opening member and air pressure after the air has passed through the opening member in the air duct ; and an opening member replacing mechanism that forms a part of the air duct , the opening member replacing mechanism being configured to allow the opening member to be replaceable, wherein the measurement device further comprises a controller coupled to the pressure sensors , the controller being configured to calculate the airflow volume and the ventilation resistance of the wind-blowing apparatus using measurement values of the air pressures before and after the air passes through the opening member , the controller being configured to display the calculated airflow volume and ventilation resistance on a display , and wherein the controller is configured to calculate the airflow volume on the basis of the second differential pressure and to calculate the ventilation resistance on the basis of the calculated airflow volume and the first differential pressure. a housing that includes an air duct with an air inlet and an air outlet , the air inlet being configured to take in air, the air outlet being configured to send out the taken air; a straightening grid configured to straighten the air taken from the air inlet , an opening member installed inside the air duct , the opening member including an opening allowing the air taken from the air inlet to pass therethrough; a first differential pressure sensor configured to measure a first differential pressure between air pressure from the air inlet to straightening grid before the air passes through the straightening grid and atmospheric pressure of the outside air obtained through an outside air-port ; a second differential pressure sensor configured to measure a second differential pressure between air pressure from the straightening grid to the opening member before the air passes through the opening member and air pressure after the air has passed through the opening member in the air duct ; and an opening member replacing mechanism that forms a part of the air duct , the opening member replacing mechanism being configured to allow the opening member to be replaceable, wherein the measurement device further comprises a controller coupled to the pressure sensors , the controller being configured to calculate the airflow volume and the ventilation resistance of the wind-blowing apparatus using measurement values of the air pressures before and after the air passes through the opening member , the controller being configured to display the calculated airflow volume and ventilation resistance on a display , and wherein the controller is configured to calculate the airflow volume on the basis of the second differential pressure and to calculate the ventilation resistance on the basis of the calculated airflow volume and the first differential pressure. <EOS>