In a post on Instagram, the 26-year-old US singer revealed she has named the new arrival Ender Ridley Aydin.
She shares the child with music producer Alev Aydin.
Halsey wrote on Instagram: “Gratitude. For the most ‘rare’ and euphoric birth. Powered by love.”
She shared an image of her cradling the newborn alongside the message.
Halsey, whose real name is Ashley Frangipane, said the baby was born on July 14.
Fellow pop star Olivia Rodrigo congratulated Halsey.
She wrote on Instagram: “the most beautiful family! congratulations.”
Halsey previously said being pregnant had shifted her understanding of gender.
“I’ve been thinking lots about my body. It’s strange to watch yourself change so quickly,” she said.
“I thought pregnancy would give me very strong, binary feelings about ‘womanhood’ but truly it has levelled my perception of gender entirely.
“My sensitivity to my body has made me hyper aware of my humanness and that’s all. Doing a remarkable thing. And it’s grand. I hope the feeling lasts.”
Pop star Halsey says she feels ‘gratitude’ after the birth of her first child