A screen printing machine configured to print solder onto a surface of a circuit board using a screen mask, the screen printing machine comprising: said screen mask arranged at a top side of the circuit board; a box member arranged at an underside of the circuit board including a space that is closed by the circuit board; a clamp device configured to clamp the circuit board on un upper surface of the box member such that the circuit board does not move relative to the box member, a raising and lowering device configured to raise and lower the circuit board loaded on the upper surface of the box member with respect to the screen mask, a printing device configured to print solder onto the circuit board via the screen mask in a state with the screen mask arranged on the surface of the circuit board loaded on the upper surface of the box member, a negative pressure generator connected to said space of the box member and configured to create negative pressure inside said space; a sensor configured to detect a pressure inside said space; and a control device configured to control the negative pressure generator based on the pressure detected by the sensor; and an input section configured to receive an input of a set pressure value, wherein the control device controls the negative pressure generator such that a pressure value of the pressure detected by the sensor is the set pressure value, characterized in that the set pressure value is able to be classified as a first set value set as the pressure value inside said space when the circuit board is clamped by the clamp device, a second set value set as the pressure value inside said space when solder is being printed onto the circuit board by the printing device, and a third set value set as the pressure value inside said space when the circuit board is separated from the screen mask by the raising and lowering device, the input section is configured to receive an input of the first set value, the second set value, and the third set value, and the control device is configured to perform control such that the pressure inside said space when the circuit board is clamped by the clamp device makes the pressure value inside said the space the first set value, perform control such that the pressure inside said space when solder is being printed onto the circuit board by the printing device makes the pressure value inside said space the second set value, and perform control such that the pressure inside said space when the circuit board is separated from the screen mask by the raising and lowering device makes the pressure value inside said space the third set value. said screen mask arranged at a top side of the circuit board; a box member arranged at an underside of the circuit board including a space that is closed by the circuit board; a clamp device configured to clamp the circuit board on un upper surface of the box member such that the circuit board does not move relative to the box member, a raising and lowering device configured to raise and lower the circuit board loaded on the upper surface of the box member with respect to the screen mask, a printing device configured to print solder onto the circuit board via the screen mask in a state with the screen mask arranged on the surface of the circuit board loaded on the upper surface of the box member, a negative pressure generator connected to said space of the box member and configured to create negative pressure inside said space; a sensor configured to detect a pressure inside said space; and a control device configured to control the negative pressure generator based on the pressure detected by the sensor; and an input section configured to receive an input of a set pressure value, wherein the control device controls the negative pressure generator such that a pressure value of the pressure detected by the sensor is the set pressure value, characterized in that the set pressure value is able to be classified as a first set value set as the pressure value inside said space when the circuit board is clamped by the clamp device, a second set value set as the pressure value inside said space when solder is being printed onto the circuit board by the printing device, and a third set value set as the pressure value inside said space when the circuit board is separated from the screen mask by the raising and lowering device, the input section is configured to receive an input of the first set value, the second set value, and the third set value, and the control device is configured to perform control such that the pressure inside said space when the circuit board is clamped by the clamp device makes the pressure value inside said the space the first set value, perform control such that the pressure inside said space when solder is being printed onto the circuit board by the printing device makes the pressure value inside said space the second set value, and perform control such that the pressure inside said space when the circuit board is separated from the screen mask by the raising and lowering device makes the pressure value inside said space the third set value.