A component mounter comprising: a characteristic value measuring device that is configured to measure a characteristic value of a first component; and a head configured to mount at least the first component and a second component on the same board; the component mounter being characterized in that the second component is a digital potentiometer provided with a receiver section configured to receive information from the head, a variable resistance section for which a resistance value is variable, and a control section configured to control the resistance value of the variable resistance section, the mounting head is provided with a receiver section configured to receive information from the characteristic value measuring device, a sender section configured to send information to the second component, a power source configured to supply current to the variable resistance section, a memory section in which is memorized the resistance value of the second component corresponding to the characteristic value of the first component, and a control section, and wherein the control section of the head is configured to receive the characteristic value of the first component measured by the characteristic value measuring device from the characteristic value measuring device via the receiver section, to identify the resistance value of the second component from the memory section based on the received characteristic of the first component, and to send the identified resistance value of the second component to the second component via the sender section, the power source of the head is configured to supply electric current to the variable resistance section of the second component, and the control section of the head, with respect to the control section of the second component, is configured to receive the resistance value of the second component received from the head via the receiver section of the second component, and with electric current flowing in the variable resistance section, to adjust the resistance value of the variable resistance section based on the received resistance value of the second component. a characteristic value measuring device that is configured to measure a characteristic value of a first component; and a head configured to mount at least the first component and a second component on the same board; the component mounter being characterized in that the second component is a digital potentiometer provided with a receiver section configured to receive information from the head, a variable resistance section for which a resistance value is variable, and a control section configured to control the resistance value of the variable resistance section, the mounting head is provided with a receiver section configured to receive information from the characteristic value measuring device, a sender section configured to send information to the second component, a power source configured to supply current to the variable resistance section, a memory section in which is memorized the resistance value of the second component corresponding to the characteristic value of the first component, and a control section, and wherein the control section of the head is configured to receive the characteristic value of the first component measured by the characteristic value measuring device from the characteristic value measuring device via the receiver section, to identify the resistance value of the second component from the memory section based on the received characteristic of the first component, and to send the identified resistance value of the second component to the second component via the sender section, the power source of the head is configured to supply electric current to the variable resistance section of the second component, and the control section of the head, with respect to the control section of the second component, is configured to receive the resistance value of the second component received from the head via the receiver section of the second component, and with electric current flowing in the variable resistance section, to adjust the resistance value of the variable resistance section based on the received resistance value of the second component.