A flow rate control apparatus includes a flow rate detection unit that detects the flow rate of a fluid flowing through a solenoid valve, a correlation storage unit that stores a correlation between a flow start point voltage at which the fluid starts to flow through a sample solenoid valve, which has substantially the same characteristic as the solenoid valve, and a limit voltage at which the sample solenoid valve is fully open, and a control unit that, when starting control of the flow rate of the fluid, changes the driving voltage of the solenoid valve, obtains the driving voltage at a time when the start of flowing of the fluid is detected as the flow start point voltage, and uses the correlation for the sample solenoid valve to set the driving voltage of the solenoid valve within a range between the flow start point voltage and the limit voltage.