Outside Beijing's busy Hailong Electronics Market, thousands of Chinese - many of them students - chant slogans like "Boycott Japanese Products" and "Down with the Japanese."
The demonstration Saturday comes after Japan this week approved a controversial school textbook that omits some 20th century Japanese aggression against China and other Asian nations.
The anger here on the streets of Beijing is palpable. Some of these protesters burned Japanese flags, to the delight of onlookers who clapped and cheered.
Resentment has simmered in China for decades over the Japan's failure to apologize for actions during World War II, but recent events - such as the textbook issue - have reignited anger.
Some demonstrators say this makes them worry about Japan's attempts to secure a permanent seat on the United Nations Security Council.
Political protests are rare in China. However, unarmed police watched Saturday's crowds passively. Many participants had received news of the protest by text message or e-mail. Some students said their universities and schools had encouraged them to attend.
Beijing University student, An Nao Ling, says it is time to take action.
He says the protest is intended to mobilize all Chinese citizens to boycott Japanese products.
Some demonstrators took pains to explain that they are upset with Japanese government. Beijing resident Geng Jing says she has no personal hostility towards the Japanese people.
She says she does not know any Japanese people personally, so cannot say whether they are anti-Chinese. But she thinks the Japanese government is very unfriendly towards China.
Chinese resentment against Japan is not limited to Beijing residents. Last week, protesters in the southwestern city of Chengdu smashed windows in a Japanese department store.
State-run media have also reported that millions of Chinese citizens have signed an online petition against Japan gaining a seat on the United Nations Security Council.