A management device that transmits data to a plurality of terminal devices by way of communication relay devices on a connected communication network and controls the plurality of terminal devices includes a transmission data storage section and a communication control section. The transmission data storage section stores transmission data. The communication control section controls communication with the terminal devices. The communication control section issues start notification of data transmission in one-to-one communication to each terminal device that is a transmission target of the terminal devices, and receives a response from the terminal device in response to the start notification, starts transmission of the transmission data in one-to-multiple communication after the start notification, and issues, after completion of the transmission of the transmission data, a transmission request of a reception status of the transmission data in one-to-one communication to a terminal device that has responded to the start notification.