The Calder Cup is awarded annually to the playoff champion of the American Hockey League. The trophy is the worlds second oldest (after the NHL Stanley Cup) continuous professional ice hockey championship, having first been awarded in 1937 following the 1936-37 AHL season, and continuously being awarded every year.

The cup is named after Frank Calder, who was the first president of the National Hockey League. The Calder Memorial Trophy, which is awarded annually to the Rookie of the Year in the National Hockey League, was also named after Calder.

The Hershey Bears have won the Cup more times than any other team, with eleven victories in franchise history. The Cleveland Barons (Cleveland Barons (1937-1973)) come in second with nine; the Springfield Indians/Kings (Springfield Indians) are third with seven. Eight teams have won back-to-back championships; the Springfield Indians of 1960-62 is the only team to have won three straight Calder Cup championships.

On three occasions an AHL club has won the Calder Cup and its NHL affiliate also won the Stanley Cup. In both 1976 and 1977 the Montreal Canadiens and affiliates Nova Scotia Voyageurs won both trophies. In 1995, the New Jersey Devils and Albany River Rats achieved the same feat.

The playoff MVP is awarded the Jack A. Butterfield Trophy. The current Calder Cup champions are the Hershey Bears.