A robot system (1) includes a multi-jointed robot (20), a syringe actuator (30) which pulls and pushes a plunger (17c) of a syringe (17) having a needle (17e), and the controller (100) which controls operation of the multi-jointed robot (20) to handle a vial (16) and the syringe (17) and controls the syringe actuator (30). The controller (100) performs: (A) control of the multi-jointed robot (20) such that the needle (17e) of the syringe (17) punctures a cap (16c) of the vial (16) after the control described in A, (B) control of the syringe actuator (30) such that a liquid in the vial (16) is absorbed through the needle (17e) by pulling the plunger (17c) and after the control described in A, (C) control of the multi-jointed robot (20) such that the needle (17e) is inclined with respect to the cap (16c) of the vial (16) by changing an orientation of at least one of the vial (16) and the syringe (17).
