A Queens park that got high grades in a new report is no bed of roses, local activists say.

Little Bay Park earned an A-plus in a New Yorkers for Parks report released yesterday, including a grade of 93 for its bathrooms.

But “there’s no bathrooms,” said local park advocate Alfredo Centola.

Instead, the 55-acre park in Bayside has dingy port-a-potties — including one that was set on fire, leaving it melted into the weeded ground.

“If they consider bushes bathrooms, they can get a 93,” Centola said.

He said the park also needs more drinking fountains — despite scoring a 100 in that category — and better lawns and athletic equipment. The park has only two fountains, and none worked yesterday.

The playing fields are currently uneven, and filled with holes, a Post reporter found. Crossbars on soccer goals were bent, and the goals’ netting were ripped to shreds.

“There are flooding conditions the minute it rains,” said Centola. “Even in light rains, the kids playing on the soccer field slip in mud.”

Holly Leicht, executive director of New Yorkers for Parks — which is listed on the city Parks Department Web site as a “partner” of the agency — said surveyors examined the parks in the summer.

She acknowledged conditions might have changed.

“These scores are a snapshot in time,” she said.

New Yorkers for Parks surveyed 43 parks in the city last year ranging from 20 acres to 500 acres. Together, they scored an average of a B-plus rating for maintenance, up from a B in 2011.

Judi Francis, co-chair of the NYC Sierra Club’s parks committee and a Brooklyn activist, said she’s not taking the grades serious.

“They looked at many of top 40 or so larger parks in the city,” Francis said. “But what about the lower 40 — the ones that are not shiny examples that Mayor Bloomberg wants to show off?”

But New Yorkers for Parks said it uses “an objective methodology to determine the parks surveyed,” adding it’s an independent group and that any suggestion that it “would only survey certain parks to make the administration look good is absurd.”