There were angry scenes at the meeting at Gloucestershire County Cricket ground on Tuesday, with one councillor tweeting: "It's all kicking off".
Security staff had initially stopped protesters from entering, although eventually let them in.
Avon and Somerset Police said no crimes were found to have been committed.
The meeting was attended by people protesting on various issues including those opposed to a US trade deal - TTIP -  and others fighting the closure of the Hawkspring drug and alcohol charity.
But some were initially blocked from getting into what was the last full meeting of the council before the mayoral elections in May.
At the meeting, Green councillor Rob Telford tweeted people were trying to "storm the room" adding: "It's all kicking off". Labour's Fabian Breckels tweeted: "Bit of a disturbance at Full Council ... TTIP protesters have been denied entry".
One man said he had been "manhandled" by security guards.
Conservative councillor Chris Windows told the BBC his car had been kicked by a man "shouting abuse" outside the meeting.
A spokesman for Avon and Somerset Police said: "We were called at 5.46pm to County Ground Lodge on Nevil Road, it was a report of a disturbance but when officers arrived there were no ongoing issues and no offences were found to have been committed."
Bristol City Council has been contacted for comment. Gloucestershire County Cricket Club said the council provided the security for the event.
Police were called to reports of a disturbance at a Bristol council meeting to which protesters were temporarily denied access.