Campaigners have vowed to fight the latest application to turn playing fields into a touring caravan site.
Last week Harrow Community Sports Ltd submitted plans to Harrow Borough Council for Broadfields playing fields, in Headstone Lane.
The firm last year withdrew a similar application days before a decision was due.
There was strong opposition from people living near the fields with the Save Broadfields Campaign collecting more than 4,000 signatures against the proposals.
Campaigner Georgia Weston said: “We had a feeling these plans would come back again. But with a new application comes a new campaign.
“I think last time the size of the petition showed the strong sense of feeling about these playing fields and the community does not want a caravan site.
“We want Broadfields to remain for sport and recitation use. There is a need for playing fields in the borough and a huge appetite for sport in the area.
“We will be tackling this campaign with as much energy and before to make sure these fields are for sporting use only.”
The proposals include the creation of 75 pitches and the building of toilet and shower blocks.
Owner Richard Gabriel told the Harrow Times there is a demand for touring caravan sites in North West London and using the site for sport is no longer financially viable.
He said it was an appropriate use of the site and the alternative would be for the company to sell the site.