A liquid supplying mechanism comprising: a storage unit that is arranged to store a liquid; a supply line (58, 74, 98) that is arranged to supply a liquid from the storage unit to a jetting unit that discharges the liquid from a nozzle surface thereof; a discharge line (64, 66, 76) that is arranged to discharge the liquid from the jetting unit to the storage unit; a first detecting unit that is arranged to detect a supply pressure of the liquid within the supply line (58, 74, 98); a second detecting unit that is arranged to detect a discharge pressure of the liquid within the discharge line (64, 66, 76); a first pressure adjusting unit that is arranged to adjust the supply pressure of the liquid within the supply line (58, 74, 98); a second pressure adjusting unit that is arranged to adjust the discharge pressure of the liquid within the discharge line (64, 66, 76); and a control unit configured to control the first pressure adjusting unit and the second pressure adjusting unit by control parameters each having a given initial value on the basis of the supply pressure detected by the first detecting unit and the discharge pressure detected by the second detecting unit, respectively, so that the supply pressure is higher than the discharge pressure while a back pressure at the nozzle surface is maintained at a given value, characterised in that: the control unit is further configured, when deviations of the detected supply pressure and the detected discharge pressure with respect to the corresponding target pressure value exceed a given reference value, to control each of the first pressure adjusting unit and the second pressure adjusting unit by changing the control parameters from the initial values; and in that the liquid supplying mechanism further comprises: a pressure fluctuation unit that is arranged to fluctuate the supply pressure and the discharge pressure so that the deviations of both of the pressures with respect to the target pressure value exceed the given reference value, wherein the control unit is further configured to change the control parameters to control each of the first pressure adjusting unit and the second pressure adjusting unit, temporarily fluctuate the supply pressure and the discharge pressure by the pressure fluctuation unit, and then determine the deviations of the detected supply pressure and the detected discharge pressure with respect to the corresponding target pressure value, respectively. a storage unit that is arranged to store a liquid; a supply line (58, 74, 98) that is arranged to supply a liquid from the storage unit to a jetting unit that discharges the liquid from a nozzle surface thereof; a discharge line (64, 66, 76) that is arranged to discharge the liquid from the jetting unit to the storage unit; a first detecting unit that is arranged to detect a supply pressure of the liquid within the supply line (58, 74, 98); a second detecting unit that is arranged to detect a discharge pressure of the liquid within the discharge line (64, 66, 76); a first pressure adjusting unit that is arranged to adjust the supply pressure of the liquid within the supply line (58, 74, 98); a second pressure adjusting unit that is arranged to adjust the discharge pressure of the liquid within the discharge line (64, 66, 76); and a control unit configured to control the first pressure adjusting unit and the second pressure adjusting unit by control parameters each having a given initial value on the basis of the supply pressure detected by the first detecting unit and the discharge pressure detected by the second detecting unit, respectively, so that the supply pressure is higher than the discharge pressure while a back pressure at the nozzle surface is maintained at a given value, characterised in that: the control unit is further configured, when deviations of the detected supply pressure and the detected discharge pressure with respect to the corresponding target pressure value exceed a given reference value, to control each of the first pressure adjusting unit and the second pressure adjusting unit by changing the control parameters from the initial values; and in that the liquid supplying mechanism further comprises: a pressure fluctuation unit that is arranged to fluctuate the supply pressure and the discharge pressure so that the deviations of both of the pressures with respect to the target pressure value exceed the given reference value, wherein the control unit is further configured to change the control parameters to control each of the first pressure adjusting unit and the second pressure adjusting unit, temporarily fluctuate the supply pressure and the discharge pressure by the pressure fluctuation unit, and then determine the deviations of the detected supply pressure and the detected discharge pressure with respect to the corresponding target pressure value, respectively. a pressure fluctuation unit that is arranged to fluctuate the supply pressure and the discharge pressure so that the deviations of both of the pressures with respect to the target pressure value exceed the given reference value, wherein the control unit is further configured to change the control parameters to control each of the first pressure adjusting unit and the second pressure adjusting unit, temporarily fluctuate the supply pressure and the discharge pressure by the pressure fluctuation unit, and then determine the deviations of the detected supply pressure and the detected discharge pressure with respect to the corresponding target pressure value, respectively.