The pair will lead the party to Vancouver, where they will play Canada on June 14 and the USA on June 21, with a potential final on June 28 at The Thunderbird Stadium.
The squad will then head on to Tokyo to face Japan in friendly encounter at the National Stadium on July 5.
Former England fullback Mallinder and ex-hooker Diamond have taken the Cheshire club to second in the Zurich Premiership and last season Sharks won the Parker Pen Shield, the first piece of major silverware in their 142-year history.
"We are very pleased to be on board and excited to be given this opportunity," said Mallinder. "This tour is vital for the development of English players and it is a great opportunity for some of them to come through and shine.
"Steve and I work well together at Sharks and I hope we can bring that partnership to England.
As in June 2001, when England won all three internationals and two midweek matches on their North American tour while many of their players were with the British Lions in South Africa, the team that participates in the Churchill Cup and the game in Japan will contain several players pushing hard for World Cup places.
England head coach Clive Woodward said: "The Churchill Cup will provide all of the players taking part with a huge challenge at international level. Jim Mallinder and Steve Diamond are doing a great job with The Sharks and I am delighted that they will be leading the party.
"I must stress that the tournament will be an important part of our World Cup preparations and that there will be players on the tour that will be part of the squad in October.
"I saw at first hand the progress Canada and the USA are making during our North American tour in 2001 and I’m delighted that this is continuing."