The present invention provides terminal roaming supported method in mobile radiated television service. It contains 1, visiting area mobile communication network side receiving terminal sent service authorizing request message, querying whether pre - saving said terminal user encryption key, if it is then executing steps 3 otherwise executing steps 2, 2, visiting area mobile communication network side transmitting user encryption key obtaining request message to attributed area mobile network side, obtaining attributed area mobile network side returned said terminal user encryption key, 3, visiting area mobile communication network side querying said terminal user corresponded order information, according to said user order information, judging whether said terminal user ordering said radiated television program and executing relevant operation. Said invention also provides terminal roaming supported system in mobile radiated television service and supports terminal roaming, service authentication and charging in mobile radiated television service. |