She has been England's Queen for 57 years, longer than President Obama has been alive. While he's been described as "nervous but excited" about the meeting, English historian David Starkey says it's unlikely the Queen feels the same way.
"She's seen it all before," Starkey said. "She has seen 11 presidents come and go ,and met 10 of them."
The exception was Lyndon Johnson. Busy with Vietnam and domestic matters, Johnson never went to England, while pregnancy and children kept the queen from traveling.
She was still a princess when she met Harry Truman, president number thirty-three, but her first.
Subsequent presidential meetings have had high points - and low ones.
She got along famously with President Reagan and even went horseback riding with him at Windsor Castle. Another 1982 visit began a little awkwardly however, when Mr. Reagan insisted his wife, Nancy, walk in front of him. Royal protocol required that she walk behind, next to the queen's spouse. Finally, they all walked in line together.
She turned into a talking hat when meeting the first President Bush in 1991. The microphone stand that was just right for the six-foot-two president, overwhelmed the five-foot-four monarch.
During a D-Day commemoration dinner in 1994, President Clinton's relationship with Queen Elizabeth turned a bit cold. It appeared he virtually ignored Queen Elizabeth while being very attentive to Belgium's Queen Paola.
Gerald Ford's gaffe happened at a 1976 state dinner. Just as the queen began to dance, the Marine Band struck up "The Lady is a Tramp."
"She's said to have a very robust sense of humor, with, it's said, a coarse edge," said Starkey. "I suspect she found it hilarious."
The second President Bush made two faux pas during a 2007 South Lawn welcome. First, he made her quite a bit older.
"You helped our nation celebrate its bicentennial in 177 - uh, in 1976," Mr. Bush said.
And then he winked at her.
"She gave me a look that only a mother could give a child," President Bush joked, trying to break the tension.
But Starkey anticipates smooth sailing for President Obama when he meets with the Queen Wednesday at Buckingham Palace.
"Provided he remembers she is a lady, I'm sure he's good at that," the historian said, "He has chivalry as well as charm, he'll be fine."
By Katie Couric