The present invention controls liquid jetting by use of a novel control index. Provided is a liquid jetting device which causes periodical changes in the flow rate of a liquid being jetted out, wherein: in the case of a first setting, the liquid jetted out within one cycle of the periodical changes applies an impulse represented by a first value to an object onto which the liquid is jetted； and, in the case of a second setting different from the first setting, the liquid jetted out within the one cycle applies an impulse, of which the magnitude equals a second value, to the object onto which the liquid is jetted.本發明之課題係藉由新控制指標控制液體噴射。 本發明之液體噴射裝置係使噴射之液體之流速週期性變動者，且於第1設定之情形，於上述週期性變動之1週期量噴射之液體對噴射對象物賦予第1值之衝量，於與上述第1設定不同之第2設定之情形，於上述1週期量噴射之液體對上述噴射對象物賦予第2值之衝量。
