Robin Corrente says she was wearing her black Coco Reef swimsuit in her backyard in temperatures of 32C and the underwiring became so hot she had to be treated in hospital for burns.
Ms Corrente, 50, of Yaphank said: “After about an hour, I was hurting. I went up to take a shower and I realised ... I had a lot of blisters.
She added that doctors confirmed she had suffered burns and they had to remove a piece of flesh "the size of a dime" from her right breast.
Corrente is suing Coco Reef manufacturer Swimwear Anywhere in Manhattan Supreme Court.
Coco Reef specialise in swimwear for the more curvaceous woman.