Protesters supporting the spiritual group Falun Gong, which is banned in China, lined motorcade entry points into the convention centre area.
Nearby, dozens of supporters and opponents of Chinese policies faced off, Chinese flags on one side and a banner calling the Chinese Communist Party a “virus” on the other, separated by police lines.
Supporters of China also turned out near where Biden and Xi will meet, waving Chinese and US flags as well as posters with both flags together.
Thousands of police lined streets near the San Francisco convention centre, and protests in the days before Biden and Xi’s meeting have been relatively peaceful, with some crowds stretching for blocks, including a march uniting several interest groups on Sunday.
San Francisco has cleaned up downtown streets for the meeting, and it has prepared for a potential confrontation with demonstrators: eight-foot high metal mesh barriers have been erected to keep people on sidewalks from interfering with vehicle traffic near the convention centre.
The potential for disruptions around the summit site in downtown San Francisco, portions of which will be shut to vehicles and foot traffic, led the US Department of Homeland Security to designate the meeting a national special security event, putting the US Secret Service in charge of the coordination of policing agencies.