A printer 1 serving as a liquid ejection device includes: a device body 2 including a recording head 20 that ejects ink; a scanner unit 3 that closes and opens at least a portion of an upper portion of the device body 2; and a plurality of ink tank 10 that are provided in the device body 2, each contain ink to be supplied to the recording head 20, and each include an ink injection port 26 through which the ink can be injected from a liquid supply container. At least one of the plurality of ink injection ports 26 is located inside an opening and closing region that is opened and closed by the scanner unit 3, and the other ink injection ports 26 are located outside the opening and closing region.