The city government said his work as a presenter of a state-sponsored programme on Iranian television was incompatible with his duties in Rotterdam.
Tariq Ramadan is a professor of Contemporary Islam Studies at Oxford, a post which he has held for the past four years.
The British university said in a statement that freedom of expression is a fundamental right. Yet the university adds that it disagrees with Ramadan's views.
The Swiss-Egyptian islamologist also lost his job as a visiting professor at Rotterdam's Erasmus University.
Ramadan is furious about his dismissal from his jobs in Rotterdam and is taking the city to court. In his view, the decisions were politically motivated and inspired by the current wave of anti-Islamic sentiments in the Netherlands.