Representatives from various European women's groups met in London for a symbolic burial of the Olympic Charter, saying its principles of condoning any form of discrimination and upholding equality of men and women had been decimated.
Annie Sugier, spokeswoman for the International League of Women's Rights, acknowledged progress has been made with all countries to have female athletes on their teams at London for the first time and women boxers making their debut, ending the last all-male sport at the summer Games.
But she said at the London Games, starting Friday and running until August 12, women are competing in 30 fewer events than men and only 132 gold medals are available to women compared to 162 for men.
"It is clear that more needs to be done as there is still gender discrimination at the Olympics," Sugier told Reuters.
"The Olympic Games play a critical role in building a better world and are more than just a sports competition. This is the one place in the world where there are no borders and one law for all and that can lead to change in society."
The demonstrators, uniting under the banner "London 2012: Justice for Women", drafted seven demands to be included in a letter delivered to all IOC members on Wednesday.
The list included having the same number of medal events for men and women, ensuring women held 50 percent of positions in leading sports bodies, and enforcing neutrality in sport by banning the wearing of political or religious symbols.
An IOC spokeswoman told Reuters that there had been a real momentum towards gender equality in sport over the past 30 years with statistics showing that more women were taking part.
"As a general rule, the IOC strives to ensure the Olympic Games and the Olympic Movement are universal and non-discriminatory, in line with the Olympic Charter and our values of respect, friendship and excellence. National Olympic Committees (NOCs) are encouraged to uphold that spirit in their delegations," she said.
"We would hope that London will see the highest percentage of female participation in history," she added.
Anne-Marie Lizin, honorary president of the Belgian Senate, said it was disappointing the IOC had allowed some countries, including Saudi Arabia, to only allow female athletes to compete if they covered themselves up.
At the Beijing 2008 Olympics, 14 countries had veiled women.
"We want all women in all countries of the world to have access to sport, to be able to complete and have the possibility of coming to the Olympics - and to wear what they want," said Lizin.
The demonstrators called for women's sports to be given the same profile as men's sports, citing the medal ceremony for the men's marathon as a key example.
IOC President Jacques Rogge presents the gold medal to the men's marathon winner but not to the winner of the women's race.
"It is outrageous that the IOC president will present the gold medal for the men's marathon but not for the women's," said human rights campaigner Peter Tatchell of the Peter Tatchell Foundation. "Discrimination against women is particularly acute at the Olympics."
However, Britain's Women's Sport and Fitness Foundation (WSFF), a charity that aims to make women active and confident, praised the London Olympics for being the most women-friendly to date with women outnumbering men on the U.S. and Canadian teams.
Sue Tibballs, CEO of WSFF, said her organization has launched a Twitter hashtag, #gogirl, to build support for the British women athletes.
"There is an important point to be made. Female role models are essential to inspire young girls to be more active, particularly in a culture that tells them that it is more important to be thin than fit," said Tibballs.