A liquid injection device includes an injection unit which injects a liquid, a liquid supply instrument which supplies the liquid to the injection unit, and a control unit which controls operation of the injection unit and the liquid supply instrument, wherein the injection unit includes a distal end portion where a nozzle for injecting the liquid is formed, and a body portion in which the distal end portion is removably loaded, at the distal end portion, a distal end-side memory is provided in which first startup data is written, and the control unit is a control unit which reads and writes the first startup data from and to the distal end-side memory in the distal end portion loaded in the body portion and manages use time of the distal end portion based on the first startup data that is read out.