"The are 16 million children struggling with hunger in America. That's one in five daughters, sons, neighbours and classmates who don't know where their next meal is coming from, yet billions of pounds of good food go to waste every year. It's time we do something about it.
"Together we can solve hunger. Together we're feeding America."
The 30-year-old actress' Avengers co-star Jeremy Renner - who has a two-year-old daughter, Ava, with estranged wife Sonni Pacheco - has also recorded a PSA for charity Feeding America.
He said in his clip: "As an American, it's hard to hear that we have a serious hunger issue in our country. And as a parent it's even harder to hear one in five of our kids struggles with hunger, especially when billions of pounds of good food are wasted every year."
Johansson - who has seven-month-old daughter Rose with husband Romain Dauriac - has previously admitted her upbringing in Manhattan's Greenwich Village saw her family have "little money".
- Bang! Showbiz