A teen badly injured when she was doused with acid at an East Village party in May is calling on cops to catch the person who left her with debilitating third-degree burns.

Ava Aldrich, 18, spent two nights in the ICU at Weill Cornell Medical Center and underwent skin-graft surgery in June after she was among a dozen teens burned when drain-clearing sulfuric acid was thrown at them during a party at a NYCHA development.

“It was extremely painful,” the young Manhattan woman told The Post. “I felt like my legs were burning. I saw holes in my jeans, and it was eating into my skin.”

Aldrich and more than 100 other teens had shown up at the First Houses on East Third Street on May 4 for a party advertised on social media when paint and a caustic substance — later revealed to be an industrial drain cleaner — started raining down on them from above at around 10 p.m.

Witnesses said it came from a fourth-floor apartment which overlooks an outdoor entrance to the basement where the party was held, according to law-enforcement sources.

At least 10 teens between ages 15 and 18 were hospitalized with minor burns — but Aldrich was severely injured.

She suffered third-degree burns to her legs and will have to wear compression bandages 23 hours a day for at least the next nine months.

“I’m obviously frustrated because they can’t arrest who did this,” said Aldrich, a recent Eleanor Roosevelt HS graduate.

She plans to attend the University of California Santa Cruz next year, and will spend her first year of college in the bandages.

Detectives from the Ninth Precinct have talked to several people who were in the apartment at the time, but they denied throwing anything, law-enforcement sources said.

A 911 call came from the same apartment, they said. But without someone identifying the attacker, it will be hard to make an arrest.

“It’s hard to not think about it all the time,” Aldrich said. “I just try to deal with it, but sometimes, I’ll get upset or angry.

“I’m not really the person to be like, ‘Why did this happen to me?’ I was in the wrong place at the wrong time,” she said.

Her mom, Amy Aldrich, praised her daughter’s bravery but said the past three months had been “really terrible” for the family.

“Just about every medical professional, when they see her legs, say, ‘Why hasn’t someone been caught?’ ” the mom said.

Crime Stoppers is offering a $2,500 reward for information on the assault. Anonymous calls may be made to (800) 577-TIPS.