Disclosed is an electronic device performing a video transmission using a multi-wireless network and a controlling method thereof. The electronic device for receiving and reproducing contents includes: a communicator, and a processor to receive, from an external device, a signal including original data of contents through a main frequency band, and receive, from an external device through at least one sub frequency band, a connection state signal including information on original data, and control the communicator to transmit, to the external device through the main frequency band and the at least one sub frequency band, a response signal including information on whether original data is missing, and an amount of received data stored in a buffer.