Firefighters based at the fire station nearby had heard shouting in the street and went out to investigate, where they were confronted and threatened by the man.
The 26-year-old suspect remained hostile and struck the window of one of the first police cars when they arrived.
Eyewitness Jenilee Graham said she was unaware there was a situation developing until a woman stopped her and told her to get away.
The 23-year-old City worker, from south London, said:
Police officers tasered an armed man in Battersea today after he threatened them.
They were called to Falcon Road when members of the public reported a man armed with a knife.
The suspect was arrested on suspicion of attempted murder of a police officer and has been taken to a south London hospital with minor injuries.
One police officer also received injuries during the incident, but did not require hospital treatment. A number of knives have been recovered at the scene.