The incident happened on a sidewalk outside the Foster Gwin Gallery in the Jackson Square neighbourhood.
In the video, gallery owner and operator Collier Gwin sprays the woman, who is sitting on the street outside his business.
San Francisco police have since confirmed they will investigate the incident, which Gwin said was the result of multiple attempts to get the woman help after he let her sleep in his doorway for days.
He also apologised for the confrontation.
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