The 'party at the palace' on Saturday July 19 will begin with music from The Shepherd Group Concert Band and finish with a Proms-style finale from the group's senior band and a fireworks display organised by Kaboom.
The programme will also feature Y Street Band performing covers of current rock and pop hits, Steel Expressions steel band and The Pepper Hearts, who will perform a 60s tribute set.
A spokesman said visitors were encouraged to bring chairs and picnic blankets, as well as a picnic. "There will be a barbecue selling burgers and hotdogs, and a bar with beers, wines and soft drinks to purchase," he said.
Judy Wilson, events fundraiser at the hospice, thanked sponsors and the Archbishop, Dr John Sentamu, who is President of the hospice, for lending the palace grounds for the event.
Admission will be by ticket only, costing £15 for adults, £5 for under 12s and under 5s free), with family tickets costing £35. Tickets are available by calling 01904 77 77 77, emailing Judy.Wilson@stleonardshospice.nhs.uk or by going to www.stleonardshospice.org.uk