The driver was still in control of the tram during the attack on November 13, which police say endangered everyone on and surrounding the tram.
The incident occurred after the man boarded the Number 16 tram outside Balaclava Train Station about 4.45pm.
Detective Leading Senior Constable Megan Fisher said the man became aggressive and verbally abusive on the tram, causing the driver to stop the tram on Chapel St in St Kilda and ask him to get off.
The man allegedly then went to the front of the carriage, reached through the driver’s window and grabbed the driver by the throat.
“He’s then squeezed her neck for several seconds,” Sen Constable Fisher said.
Several witnesses allegedly then had to pull the man away from the driver before he got off the tram and headed south along Chapel Street.
Sen. Constable Fisher said the incident placed everyone there in danger because the tram was still connected to power and being controlled by the driver.
She said the driver was left with “significant bruising” across her neck and had taken time off work due to the emotional trauma.
She said police would not accept such “abhorrent behaviour”.
“The behaviour is just cowardly, we’re not going to take it.”
Police are now searching for the man, who is believed to be aged between 40 to 50 years old and to be around six feet tall.
Police have a released of photo of a man they wish to speak to in the hope someone is able to identify him.