An online petition opposing the NSW government's plan to demolish and rebuild ANZ and Allianz stadiums at a cost of $2 billion has attracted tens of thousands of signatures.

The petition, which was posted on Change.org on Saturday evening, has struck a chord with more than 50,000 signatures added by Sunday night.

"We, the undersigned, respectfully call on the Premier of NSW, Gladys Berejiklian, and the NSW Cabinet, to reconsider their decision to knock down two perfectly fine sports stadiums," the petition reads.

"We are tired of taxpayer dollars being lavished on building facilities for sports big business, while community sport withers on the vine for lack of facilities and resources."