The liquid flow rate control apparatus includes a first flow rate control unit which includes a first flow rate control valve for a small flow rate with a first controlled flow rate range, and a second flow rate control unit which includes a second flow rate control valve for a large flow rate with a second controlled flow rate range. In particular, an overlapped range is present between the first and second controlled flow rate ranges and a liquid flows on either any one or both of the first and second flow rate control units depending on variation of a required value of a total rate. The flow rate on any one of the first and second flow rate control units is maintained and the flow rate on the other one increases while increasing the total flow rate of the liquids.