Several hundred people have been killed since protests against Saleh erupted in January.
The Security Council called on Saleh to keep a promise to immediately sign the GCC plan and for a peaceful power transition "without further delay".
Saleh has repeatedly stalled the GCC initiative that would see him step aside 30 days after it was signed in exchange for immunity from prosecution.
Karman, who was outside the Security Council for the vote, called for greater international pressure on Saleh, saying the resolution should have been tougher.
"This is not enough," she told reporters.
"We feel that the resolution did not address the issue of accountability and amnesty," she added, rejecting any suggestion of Saleh escaping prosecution.
"We reject any killing. We just want a fair trial for him. The revolution people will take Saleh in a peaceful manner. Saleh and his children will receive a fair trial," Karman said.
Karman was backed by Human Rights Watch.
"The Security Council should have more clearly distanced itself from the GCC impunity deal. By signaling that there would be no consequence for the killing of Yemenis, the immunity deal has contributed to prolonging the bloodshed," said HRW's UN representative Philippe Bolopion.
Britain's UN ambassador Mark Lyall Grant said the resolution includes some "tough messages" for Saleh and Yemen's opposition.
"We have made very clear in the resolution that all those responsible for violence, for human rights abuses should be held accountable.
"There should be no impunity for human rights abuses or the violence that has been committed. And in that respect, we entirely agree with the Nobel Prize winner," Lyall Grant said.
The Security Council went from the vote to consultations on events in Libya, including the killing of ousted strongman Moamer Kadhafi.
Diplomats said the death of Kadhafi and uprisings in other Arab nations could put pressure on the Yemeni leader. But there was no threat of sanctions in the resolution drawn up by Britain.
Russia and China this month vetoed a proposed resolution which spoke of possible measures against Syria's President Bashar al-Assad and have strongly condemned the NATO air strikes in Libya.
The Yemen resolution orders a UN report on Yemen within 30 days, and Lyall Grant said the council could quickly come back to the crisis.
The resolution "strongly condemns the continued human rights violations by the Yemeni authorities, such as the excessive use of force against peaceful protestors."
It demands that "all sides" reject the use of violence for political goals and says that all those responsible for violence, human rights violations and abuses "should be held accountable."
Saleh's refusal to hand over power since his return from medical treatment in Saudi Arabia and growing fears about the growing influence of Al-Qaeda have heightened international concern about the country.
Saleh says that if he stands down, his arch rivals, General Ali Mohsen al-Ahmar and tribal leader Sheikh Sadeq al-Ahmar, must also withdraw from Yemeni politics. The capital is now divided between forces loyal to the three rivals.