Opponents of Japan's newly-enacted national security laws held a rally in front of the parliament building in Tokyo, the media reported on Tuesday.
The laws approved on September 19 enable Japan to exercise the right to collective self-defence, public broadcaster NHK reported.
Organisers said about 9,500 people took part in the rally on Monday evening.
Protestors said they do not need laws that violate the Japanese Constitution.
A woman in her 50s said she disapproves of the new laws. She said the government should revise the Constitution if the country is to exercise the right to collective self-defence.
A 72-year-old man said he joined the rally with a strong desire not to let his children and grandchildren go to battlefields. He said he will continue to protest until the laws are scrapped.
Opponents of the laws plan to hold rallies on the 19th of every month.