Worcester City Council wants to ban the outdoor release of the balloons and sky lanterns from its land and fine those who leave their remnants behind with Â£80 fixed penalties for littering.
Opponents have taken to social media to criticise the idea as "flawed", "costly and unenforceable" and "nonsense".
The council said many other authorities had brought in similar bans.
In defence of the proposal, the council said latex balloons can persist in the environment for up to four years, while lanterns, which usually have a metal frame, could be eaten by animals.
Jabba Riaz, cabinet member for Clean, Green and Leisure Services at the Labour-run council, said: "We understand why people might view balloons and sky lanterns as a popular addition to social gatherings and events.
"However, our wildlife is clearly paying a very heavy price for this type of spectacle, and lanterns have the potential to cause serious fires.  I will therefore be voting in favour of an outright ban of their release on all council-owned land."
The policy will be debated at a cabinet meeting later.
The council said the Marine Conservation Society had called for a ban to protect wildlife, and this was supported by the RSPCA and National Farmers Union.
The Chief Fire Officers' Association called for an "urgent review" on lanterns after one sparked a huge fire at a factory unit in Smethwick, West Midlands in July 2013.
A lantern was also believed to have caused a blaze which destroyed some 100 caravans at a leisure park five months later.
A council's plan to fine people who release helium-filled balloons has been branded "utter nonsense" by critics.