Many locals say they support the move to make the city "safer and more pleasant".
Cambridgeshire County Council is considering introducing the new lower speed limits at the request of the City of Ely Council.
A public consultation on the proposals saw 122 people write to the county council in support of the plans.
However, 65 objections to the 20mph zone were also lodged, with some people arguing the change was "unnecessary".
Many of those who wrote to the county council in support of the plans said they believed the change would improve safety.
A report published by the county council said the lower speed limit could reduce the chance of accidents, and improve air quality in the city:
Installing a lower speed limit makes it an offence for motor vehicles to exceed that speed.
Lower speeds could lessen the likelihood of traffic collisions occurring and if they were to occur could lessen the impact to victims.
Lower vehicular speeds can make the environment more conducive to alternative, sustainable or active travel modes.
Lower vehicular speeds could positively affect air quality and the wider environment.
Officers at the county council said it was possible drivers could become frustrated, but said there was "insufficient evidence" to suggest this would cause more accidents, and said lower speed could result in any collisions that do happen being less severe.
The proposals are due to be considered by Ely councillors this week.