A flow rate control device for supplying liquid chemicals comprising: a housing unit which is placed at the location from which liquid chemicals are supplied and comprises an inflow conduit on one side to which the liquid chemicals flow in and an outflow conduit from which the flowed-in liquid chemicals whose flow rate is controlled flow out; and a control unit (120; 130) which is integrated with the housing unit and comprises an inflow space (124; 132) which comes in contact with an inflow hole at a terminal portion of the inflow conduit, an outflow space (128; 136) which comes in contact with an outflow hole at a terminal portion of the outflow conduit and a control path (126; 134) which is connected between the inflow space (124; 132) and the outflow space (128; 136) to control the flow rate of the flowed-in liquid chemicals, wherein the control path (126; 134) has a controlled inner diameter and a controlled length according to the flow rate a user aims at, characterized in that an outflow transport path (127; 135), through which the liquid chemicals whose flow rate has been controlled are transported, is formed between the control path (126; 134) and the outflow space (128; 136), said outflow transport path (127; 135) including inside the outflow transport path (127; 135) outflow straining protuberances (127a; 135a) at a plurality of sites at a predetermined interval so that the outflow transport path (127; 135) defines outflow passing paths (127b; 135b) through which the liquid chemicals pass, wherein said outflow straining protuberances (127a; 135a) are configured so that particles as foreign objects contained in the liquid chemicals transported by the outflow transport path (127; 135) are filtered by one of the outflow passing paths (127b; 135b) and that the rest of the particles are filtered by the rest of the outflow passing paths (127b; 135b) when the liquid chemicals are transported. a housing unit which is placed at the location from which liquid chemicals are supplied and comprises an inflow conduit on one side to which the liquid chemicals flow in and an outflow conduit from which the flowed-in liquid chemicals whose flow rate is controlled flow out; and a control unit (120; 130) which is integrated with the housing unit and comprises an inflow space (124; 132) which comes in contact with an inflow hole at a terminal portion of the inflow conduit, an outflow space (128; 136) which comes in contact with an outflow hole at a terminal portion of the outflow conduit and a control path (126; 134) which is connected between the inflow space (124; 132) and the outflow space (128; 136) to control the flow rate of the flowed-in liquid chemicals, wherein the control path (126; 134) has a controlled inner diameter and a controlled length according to the flow rate a user aims at, characterized in that an outflow transport path (127; 135), through which the liquid chemicals whose flow rate has been controlled are transported, is formed between the control path (126; 134) and the outflow space (128; 136), said outflow transport path (127; 135) including inside the outflow transport path (127; 135) outflow straining protuberances (127a; 135a) at a plurality of sites at a predetermined interval so that the outflow transport path (127; 135) defines outflow passing paths (127b; 135b) through which the liquid chemicals pass, wherein said outflow straining protuberances (127a; 135a) are configured so that particles as foreign objects contained in the liquid chemicals transported by the outflow transport path (127; 135) are filtered by one of the outflow passing paths (127b; 135b) and that the rest of the particles are filtered by the rest of the outflow passing paths (127b; 135b) when the liquid chemicals are transported.