Many of the protesters were Buddhist nuns and monks. Scuffles between police and protesters left many with bruises and minor cuts but no major injuries were reported.
"Stop killing in Tibet, We want freedom," the protesters chanted as they marched through the narrow streets of Katmandu through the tourist hub of Thamel.
Once they reached the main streets, police blocked their way and then hauled them away in vans and trucks when they tried to break past the police line.
Officials say they cannot allow protests against friendly nations, including China, and police have orders not to let the Tibetans protest in Katmandu.
The Tibetans temporarily halted their protests last month after the Tibetan government in exile - based in India - asked to them to stop because of the massive earthquake in China's Sichuan province.
They resumed protesting earlier in the week.
