He also criticised fellow African leaders without the courage to tell Mugabe to leave and said the world should tell him "the time to go is now, we are ready to give you a golden handshake if you will quit".
Mugabe, in power for nearly 30 years, has seen his reputation plummet from an African liberation hero to a despot who has ruined his once prosperous country.
Some commentators have suggested his reluctance to relinquish power, even after losing the first round of abandoned elections last year, stems from concern that he could face war crimes charges.
Odinga did not specify what the golden handshake, a term from the corporate world meaning a generous severance package, should entail.
"We are now in the face of transition (in Africa)," Odinga told delegates during a debate at the Davos forum.
"There are the remnants of the past era, the dinosaurs, and Mugabe belongs to that group."
Odinga levelled some sharp criticism at fellow members of the 15-nation Southern African Development Community (SADC) and castigated a "kid gloves" approach in dealing with Mugabe.
"The others (in SADC) do not have the courage to come up and tell Mr Mugabe that the time to leave has come," he said.
Odinga became prime minister last February after signing a power-sharing deal with President Mwai Kibaki, whom he had accused of stealing his way to victory in December polls, triggering weeks of deadly violence.