Whether or not a syringe is attached to a syringe pump is detected (Step SA1) and a motor is driven in cases in which it is detected that the syringe is attached (Step SA2). As a result the causes of minor failures from among the causes of engagement failure between a feed screw and a half nut are automatically eliminated and the frequency of the occurrence of engagement failure is reduced and in addition the operability for users is improved and the occurrence of insufficient dosing is prevented.