The Lugarno Lions Spring Festival and the Oatley Lions Village Festival have been cancelled for 2020 due to the COVID-19 health risks.
Two of the biggest community events in the Georges River community calendar, the festivals attract thousands of people from across Sydney.
The Lugarno Lions Spring Festival is believed to be the largest carnival in the southern side of Sydney outside of the Royal Easter Show, attracting between 45,000 to 50,000 people.
The Lugarno Lions 2020 Spring Festival chairman Kevin Reid said, "It is with great regret that the Lions Club of Lugarno has taken the decision to cancel the 2020 Spring Festival scheduled for 20 September 2020. The principle reason is that there are too many unknowns and far too great a risk to proceed.
"The current health crisis is too unstable to risk lives by holding an event that has the potential of many thousands of people."
The nominated date for the next festival is September 19, 2021.
The Oatley Lions Village Festival, which was due to be held in October, also been cancelled due to COVID-19 health risks.
The festival attracts about 15,000 people and has enabled Oatley Lions Club to contribute more than $170,000 in the past five years to projects, local charities, Lions Foundations and Children's Cancer Research.
"Our decision is based on keeping the community safe during these disruptive times," festival co-ordinator Richard Sheahan and Oatley Lions Club president John Morgan said in a joint statement.
"Many of the popular Festival activities are simply not feasible under current COVID-19 restrictions for mass gatherings.
"Our members are disappointed however the risks are too significant to proceed with the festival this year. "
Planning is underway for next year's festival, planned to be held on October 16, 2021.