Protesters, who say their decision on December 20 was unconstitutional, met outside their office, despite restrictions on coronavirus at meetings.
Oli says internal disputes and his party’s lack of cooperation have paralyzed decision-making, forcing him to seek a new popular mandate.
Law enforcement officers said at least 10,000 people were on the streets to join the march – one of the most intense protests the country has witnessed since Oli dissolved parliament.
“We managed the demonstration of some 10,000 protesters very tactfully,” said Basanta Bahadur Kunwar, a police spokesman.
The country’s high court will continue to hear dozens of petitions filed against Oli’s political movement in January and its plans to continue next year’s parliamentary elections on April 30 and May 10, less than two years ahead of schedule.
“The prime minister has no authority to dissolve parliament under the constitution, so he must reverse his decision immediately,” said student Rajesh Thapa, 19, waving a flag with a red hammer and sickle printed on it, a symbol of the ruling Communist Party.