Adams said in a statement provided to other media that she'd spoken to Chu and apologised.
"I got that wrong. I had thought Catherine was Chinese but I was mistaken."
Chu told Stuff she understood Adams' error.
"I was born and raised here in Christchurch and my parents are from South Korea. I can understand where the confusion came from.
"My ancestors immigrated from China to Korea a few hundred years ago and I've been really proud as a Kiwi of my multicultural background and have embraced my Korean and Chinese heritage.
"Which is why I eventually graduated university with a Bachelor of Arts majoring in Chinese."
Just after the National leadership coup which saw Simon Bridges ousted in favour of Todd Muller, new deputy leader Nikki Kaye also wrongly declared the ethnicity of a colleague.
When asked about the lack of diversity on their new front bench, Kaye wrongly said their finance spokesman was Māori.
"Paul Goldsmith is of Ngāti Porou," Kaye said, and then listed him as one of three Māori MPs in the shadow-Cabinet.
Goldsmith told journalists minutes later that while his family had "Māori connections" but he was not Māori himself.
"The Goldsmith family have many connections to Ngāti Porou. My great-great-grandfather had European wives and Māori wives so I've got lots of relatives across the Ngāti Porou but I don't claim to be Māori myself."