A droplet ejection device comprising: a droplet ejection head that is configured to eject a liquid material; a supply tank that is in communication with the droplet ejection head and a first positive pressure source ; a collection tank that is in communication with the droplet ejection head and a first negative pressure source; a replenishment tank that is in communication with the supply tank and the collection tank ; an opening/closing valve A that is configured to open and close a flow passage communicating between the supply tank and the replenishment tank ; an opening/closing valve B that is configured to open and close a flow passage communicating between the collection tank and the replenishment tank ; a switching valve configured to have a first position at which the replenishment tank and a second positive pressure source are communicated with each other and a second position at which the replenishment tank and a second negative pressure source are communicated with each other; and a control device , wherein the control device is configured to switch over to an ejection mode in which the opening/closing valve A is closed, the opening/closing valve B is closed, and the liquid material is ejected from the droplet ejection head while the liquid material is delivered from the supply tank to the collection tank ; to a replenishment mode in which the opening/closing valve A is opened, the opening/closing valve B is closed, and the liquid material is delivered from the replenishment tank to the supply tank while the liquid material is delivered from the supply tank to the collection tank ; and to a collection mode in which the opening/closing valve A is closed, the opening/closing valve B is opened, and the liquid material is delivered from the collection tank to the replenishment tank while the liquid material is delivered from the supply tank to the collection tank . a droplet ejection head that is configured to eject a liquid material; a supply tank that is in communication with the droplet ejection head and a first positive pressure source ; a collection tank that is in communication with the droplet ejection head and a first negative pressure source; a replenishment tank that is in communication with the supply tank and the collection tank ; an opening/closing valve A that is configured to open and close a flow passage communicating between the supply tank and the replenishment tank ; an opening/closing valve B that is configured to open and close a flow passage communicating between the collection tank and the replenishment tank ; a switching valve configured to have a first position at which the replenishment tank and a second positive pressure source are communicated with each other and a second position at which the replenishment tank and a second negative pressure source are communicated with each other; and a control device , wherein the control device is configured to switch over to an ejection mode in which the opening/closing valve A is closed, the opening/closing valve B is closed, and the liquid material is ejected from the droplet ejection head while the liquid material is delivered from the supply tank to the collection tank ; to a replenishment mode in which the opening/closing valve A is opened, the opening/closing valve B is closed, and the liquid material is delivered from the replenishment tank to the supply tank while the liquid material is delivered from the supply tank to the collection tank ; and to a collection mode in which the opening/closing valve A is closed, the opening/closing valve B is opened, and the liquid material is delivered from the collection tank to the replenishment tank while the liquid material is delivered from the supply tank to the collection tank . <EOS>