A liquid material filling device and method are provided which are intended to prevent air bubbles from remaining along an entire length of a flow passage extending from a liquid material reservoir (51) to a discharge port (53). The liquid material filling device includes a chamber (10) of an airtight structure, a pressure regulator (70) for regulating pressure in the chamber (10), and a control device (100). The liquid material is filled as follows. A negative pressure supply source (71) is communicated with a chamber communication pipe (90) and with a discharge device communication pipe (91) to reduce the pressure in the chamber (10) and pressure in an upper space of the reservoir (51) to a vacuum or a low pressure level close to a vacuum, and a resulted low-pressure state is maintained for a certain time to expel out air bubbles in the liquid material.