An automatic analysis device comprising: a first area with an openable/closable door in a portion thereof, in which a consumable item or a sample to be used for analysis can be supplied from outside the device with the door open; a reaction area located adjacent to the first area in which reaction using the sample is performed; a first opening/closing means for separating the first area and the reaction area in an openable/closable manner; a first air supply means or a first exhaust means for making the reaction area have a higher pressure than the first area ; characterized by : a control part for controlling drive of the first air supply means or the first exhaust means according to an open/closed state of the first opening/closing means ; a second air supply means or a second exhaust means for making not only the reaction area but also the first area have a higher pressure than outside the device, wherein pressure in the first area is adjusted so as to be lower than in the reaction area ; a measuring instrument for measuring an amount of dust in the device; and a display part for displaying an alarm to notify that dust may adhere to the consumable item , according to the measured amount of dust, wherein if the amount of dust measured by the measuring instrument exceeds a predetermined amount, the control part is adapted to drive the air supply means or the exhaust means . a first area with an openable/closable door in a portion thereof, in which a consumable item or a sample to be used for analysis can be supplied from outside the device with the door open; a reaction area located adjacent to the first area in which reaction using the sample is performed; a first opening/closing means for separating the first area and the reaction area in an openable/closable manner; a first air supply means or a first exhaust means for making the reaction area have a higher pressure than the first area ; characterized by : a control part for controlling drive of the first air supply means or the first exhaust means according to an open/closed state of the first opening/closing means ; a second air supply means or a second exhaust means for making not only the reaction area but also the first area have a higher pressure than outside the device, wherein pressure in the first area is adjusted so as to be lower than in the reaction area ; a measuring instrument for measuring an amount of dust in the device; and a display part for displaying an alarm to notify that dust may adhere to the consumable item , according to the measured amount of dust, wherein if the amount of dust measured by the measuring instrument exceeds a predetermined amount, the control part is adapted to drive the air supply means or the exhaust means . a control part for controlling drive of the first air supply means or the first exhaust means according to an open/closed state of the first opening/closing means ; a second air supply means or a second exhaust means for making not only the reaction area but also the first area have a higher pressure than outside the device, wherein pressure in the first area is adjusted so as to be lower than in the reaction area ; a measuring instrument for measuring an amount of dust in the device; and a display part for displaying an alarm to notify that dust may adhere to the consumable item , according to the measured amount of dust, wherein if the amount of dust measured by the measuring instrument exceeds a predetermined amount, the control part is adapted to drive the air supply means or the exhaust means . <EOS>