Services were scheduled to begin at 10:30 a.m. at St. Luke church.
At Smedinghoff's wake Tuesday, mourners formed long lines outside of the Oak Park Funeral Home.
The 25-year-old was killed April 6 in southern Afghanistan along with four other Americans. The group was walking from a military base to a nearby school delivering textbooks to students when a suicide bomber struck.
Sec. of State John Kerry met Smedinghoff just two weeks before her death while he was on a visit to Afghanistan.
"Anne and those with her were attacked by Taliban terrorists who woke up that day, not with a mission to educate, to help, but with a mission to destroy," Kerry said after Smedinghoff's death.
Monday, Kerry traveled to O'Hare Airport to meet privately with Smedinghoff's family.
"It was a very personal visit, and for us, very comforting and consoling. He again expressed his very personal condolences to us for the loss of Anne," said father Tom Smedinghoff.
Smedinghoff was the U.S. state department officer to die in the line of duty since the attack in Benghazi, Libya in September 2012.