For the first time, three women will serve on the International Olympic Committee's policymaking board.
El Moutawakel and Reedie were both elected unopposed to fill two vacancies for vice-president, moving up from their regular positions on the 15-member executive board.
El Moutawakel received 81 votes in favour and 10 against, while Reedie was approved with 85 in favour and four against.
El Moutawakel, who four years ago became the first woman from a Muslim nation voted onto the executive board, now becomes the first to reach the vice presidency.
She was the first woman from a predominantly Muslim nation to win an Olympic medal when she took gold in the 400-meter hurdles at the 1984 Los Angeles Games.
"I am deeply honoured," said El Moutawakel, who heads the IOC's co-ordination commission for the 2016 Olympics in Rio de Janeiro. "I will continue to promote the Olympic movement with passion and devotion and energy. You can count on me."
The Moroccan is the fourth woman to become an IOC vice-president.
Also Thursday, former Olympic fencer Claudia Bokel of Germany was elected to the executive board in her role as the new chair of the IOC athletes' commission.
Bokel becomes the third woman on the board, joining El Moutawakel and Sweden's Gunilla Lindberg — the first time three women have been on the ruling body at one time.
Of the IOC's 109 members, 21 are women. The 19.3 per cent figure is just below the 20 per cent target set by the IOC in 1996 for women's representation in international sports bodies.
Reedie, a former head of the international badminton federation, has been on the IOC board since 2009. He was a key figure in London's winning bid for the 2012 Olympics and his elevation to vice-president came just one day before the opening ceremony.
"It's a particular pleasure to be elected to this place in this city, which has taken up so much of my time in recent years," Reedie said.
El Moutawakel took the spot previously held by Yu Zaiqing of China, whose term on the board expired. Reedie replaced Italy's Mario Pescante, who resigned after Rome pulled out of bidding for the 2020 Games.
In the day's most eye-catching result, Ireland's Patrick Hickey received 34 "no" votes in his unopposed election to the board as new head of the Association of National Olympic Committees. Hickey was elected with 57 votes in favour, but the large number against underlined the continuing rancour that led to the resignation earlier this year of longtime ANOC chief Mario Vasquez Rana of Mexico.
U.S. member Anita DeFrantz and Lebanon's Tony Khoury withdrew as candidates for the executive board at the last minute because they realized their chances were slim.
"I have got more years and I wanted to be certain that I had enough votes to win," DeFrantz said. "This was too uncertain an opportunity."
It means the U.S. remains without a voice on the Olympics' most powerful body. The U.S. has been without a member on the executive board since Jim Easton left in 2006.
"We will change that," DeFrantz told The Associated Press. "Today was not the day."
The next chance will be at the IOC session in Buenos Aires, Argentina, in September 2013.
DeFrantz, who ran unsuccessfully for IOC president in 2001, has failed in several attempts to return to the executive board in recent years.
Eleven years after his father stepped down, Juan Antonio Samaranch Jr. was elevated to the executive body. After a 45-45 tie vote with Ukrainian pole vault great Sergei Bubka, the Spaniard won 50-40 in a runoff.
Bubka then ran for another seat, defeating Willy Kaltschmitt of Guatemala 51-43. Kaltschmitt returned to win the final seat, beating Nat Indrapana of Thailand 60-36.
C.K. Wu, the Taiwanese president of the international amateur boxing association, was voted onto the board as representative of the summer sports federations with 88 in favour and six against.
Swiss member Rene Fasel, head of the international ice hockey federation, was reappointed to the board as head of the winter sports with 76 in favour and 12 against.
The IOC also elected five new rank-and-file members: former Namibian sprinter Frank Fredericks, who had previously served as an athlete representative on the executive board; Japanese Olympic Committee president Tsunekazu Takeda; former badminton player Li Lingwei of China; Belgian Olympic Committee head Pierre-Olivier Beckers of Belgium; and Aisha Garad Ali, head of the Olympic body in Djibouti.