A spokesperson for the 34-year-old model and her husband, Snapchat founder and CEO, Evan Spiegel, confirmed the news to E! Online on Wednesday.
They said: “Miranda, Evan and Flynn are looking forward to welcoming the newest member of their family.”
At this time the Victoria’s Secret Angel has not announced any more details about when the child is due.
This will be the first child for the couple, who married in May this year, although Kerr already has a six-year-old son, Flynn Christopher, with her ex-husband Orlando Bloom.
Earlier this year the Australian-born mother told Vogue magazine she wanted to have siblings for Flynn, but her partner was “very traditional” and they would be waiting until after they tied the knot to extend their family.
Kerr shares custody of Flynn with her ex-Bloom, who she split with in October 2013 after three years of marriage.
Speaking to Hello! magazine, she has highlighted the importance of harmonious co-parenting and putting Flynn’s welfare first.
She said: “Orlando and I are still really close so Flynn will be with his dad for a couple of days, then when I come back, he’ll be with me so that his dad can travel. He’s always either with his dad or with me.”
Moving to Los Angeles, to live near her ex-husband, she said: “We decided as a family it was the right decision for Flynn, so Orlando and I both relocated and we live five minutes from each other.”