The plan to withhold sex from their husbands for a week will start on Monday, said Ms Isabelle Ameganvi , leader of the group's women's wing.
Ms Ameganvi, a lawyer, told the AP that her group is following the example of Liberia's women who used a sex strike in 2003 to campaign for peace.
"I am inviting all women to observe a one-week sex strike, fasting and prayers to set our arrested brothers and husbands free," said Isabelle Ameganvi, leader of the opposition Let's Save Togo. "So all you ladies have to keep the gate of your 'motherland' locked up to all men from Monday up to Sunday."
The women's protest is part of a campaign by a coalition against Mr Gnassingbé. The opposition group National Alliance for Change held a peaceful demonstration against the president on Saturday. Mr Gnassingbé has been in power since 2005, following the death of his father Gnassingbé Eyadema who ruled the West African country for 38 years.
Sex strikes have become a common way of civil disobedience in recent years. In 2009, Kenyan women pressed for a sex strike to end bickering among coalition government officials.
Last year, a group of women in a violence-plagued area of the Philippines slapped men with a sex ban until they promised to quit fighting. Their stand helped end clashes in July between villages in rural Mindanao Island.
"All you ladies have to keep the gate of your 'motherland' locked up.""We have power to change things. We do not want to remain in the kitchen, but we can have our say in politics," Ameganvi said. "We cannot stay hand-crossed, as our children and husbands are being kept in jail."
In addition to the sex strike, she called on women to wear a special color during a demonstration Thursday.
"You all have to be dressed up in red pants to show your anger," she said, amid cheers.
Togo has been led by the same family for more than 40 years.