Mr Bush announced via Twitter that he intends to make a tandem parachute jump near his summer home in Maine. It was a vow he made five years ago when he marked his 85th birthday by skydiving.
Spokesman Jim McGrath said the 41st president likes both a surprise and an adrenaline rush. He said the president hopes to show that seniors can remain active, even though he now uses a wheelchair.
A guest list for a private dinner in his honour includes more than 200 relatives and friends, a family spokesman said.
Many of the guests are from his days in the White House. His children, including former president George W Bush and former Florida governor Jeb Bush, will also be there.
During his presidential years, Mr Bush was known for jogging, tennis and fast-paced golf but now uses a wheelchair.
"He's lost his mobility, but he hasn't lost his heart. He's still the genuine person that we've come to cherish," said Ken Raynor, a friend at the Cape Arundel Golf Club.
The 41st president lives in Houston but has spent every summer at the three-storey home in Maine except when he was a naval aviator during the Second World War.
During the war, he bailed out of his airplane over the Pacific. Later, he decided to jump from a plane of his own accord and marked his 75th, 80th and 85th birthdays by skydiving.