The Thunder Bay Twins were an Amateur Senior and Professional ice hockey team from Thunder Bay, Ontario, Canada. The Twins won five Allan Cups as National Senior Champions from 1970 until 1991.

The Allan Cup is the trophy awarded annually to the senior ice hockey champions of Canada. It was donated by Sir Montagu Allan of Ravenscrag, Montreal, and has been competed for since 1909. The current champions are the Dundas Real McCoys, who captured the 2023 Allan Cup in Dundas, Ontario.