Mr Sunak, his wife Akshata Murty and their daughters Krishna, 12, and Anoushka, 10, are on a 10-day holiday in California, where they own a £5m flat.
They posed for photographs and played arcade games on the same day a group of activists staged a protest at their mansion in North Yorkshire over Mr Sunak’s climate policies.
California holds a soft spot in the couple’s hearts because it is where they met and where they once called home. The family strolled along the pier before a visit to Disneyland, where Mr Sunak said he would be taking the girls to the Star Wars attractions.
Mr Sunak said the US visit is a “really special” trip after several years without a “proper” family summer holiday.
He said his daughters were “very excited” about going to Disneyland before joking they fear they will spend too much time at the Star Wars experience because he is a fan.
Prime ministerial holiday photo shoots have a long tradition. Recent examples include David Cameron at a Portuguese fish market and Theresa May hiking in Switzerland.
California is a natural choice for Mr Sunak, who studied at Stanford and worked at a hedge fund there.
He said the place is “very special to us” as it is “where I met my wife”.
Deputy Prime Minister Oliver Dowden is at the helm in Mr Sunak’s absence, which is expected to last for just over a week.
The Prime Minister’s press secretary said he will be getting “daily updates from his private office, particularly on anything that is urgent”.
She said it would be his first time off “since he became chief secretary to the Treasury almost four years ago”.