An exogenous substance transfer apparatus (1; 11; 41; 61; 81) that introduces an exogenous substance into a cell from outside the cell by electrical action, comprising: at least one storage vessel (2; 12; 62; 82) having an opening portion (17; 18; 68; 83) through which a substance can be supplied from the outside; at least one electrode portion (5; 15; 25; 35), each of the at least one electrode portion including a pair of electrodes (5a, 5b; 15a, 15b; 25a, 25b; 35a, 35b), the at least one electrode portion disposed inside each of the at least one storage vessel, the pair of electrodes being separated from one another and extending in a direction that is intersectional to a horizontal plane; an electric field generating portion configured to generate an electric field by applying a direct current voltage to the at least one electrode portion for a specified length of time, and the electric field generating portion being configured, when applying the direct current voltage to the at least one electrode portion, to cause a liquid droplet of a cell suspension liquid to move toward an opposite polarity electrode and to cause the liquid droplet to reverse its direction of movement by causing the liquid droplet to come into contact with the opposite polarity electrode, the opposite polarity electrode being one of the pair of the electrodes whose polarity is an opposite of a polarity of the liquid droplet, the direct current voltage being applied in a state in which the cell suspension liquid has been supplied between the pair of the electrodes in each of the at least one storage vessel storing an insulating liquid to form the liquid droplet in the insulating liquid, the cell suspension liquid containing an exogenous substance and a cell, the cell suspension liquid not being capable of being mixed with the insulating liquid, and the liquid droplet having a diameter smaller than a gap between the pair of the electrodes. at least one storage vessel (2; 12; 62; 82) having an opening portion (17; 18; 68; 83) through which a substance can be supplied from the outside; at least one electrode portion (5; 15; 25; 35), each of the at least one electrode portion including a pair of electrodes (5a, 5b; 15a, 15b; 25a, 25b; 35a, 35b), the at least one electrode portion disposed inside each of the at least one storage vessel, the pair of electrodes being separated from one another and extending in a direction that is intersectional to a horizontal plane; an electric field generating portion configured to generate an electric field by applying a direct current voltage to the at least one electrode portion for a specified length of time, and the electric field generating portion being configured, when applying the direct current voltage to the at least one electrode portion, to cause a liquid droplet of a cell suspension liquid to move toward an opposite polarity electrode and to cause the liquid droplet to reverse its direction of movement by causing the liquid droplet to come into contact with the opposite polarity electrode, the opposite polarity electrode being one of the pair of the electrodes whose polarity is an opposite of a polarity of the liquid droplet, the direct current voltage being applied in a state in which the cell suspension liquid has been supplied between the pair of the electrodes in each of the at least one storage vessel storing an insulating liquid to form the liquid droplet in the insulating liquid, the cell suspension liquid containing an exogenous substance and a cell, the cell suspension liquid not being capable of being mixed with the insulating liquid, and the liquid droplet having a diameter smaller than a gap between the pair of the electrodes.