Antonia Margaret Ax:son Johnson[a] KmstkVO (Swedish: [anˈtǒːnɪa ˈâksɛlˌsɔn ˈjǔːnsɔn]; born 1943) is the fourth-generation head of the family company Axel Johnson AB, founded by her great-grandfather in 1873.

Antonia Ax:son Johnson attended Radcliffe College in Cambridge, Massachusetts, as an exchange student, and she holds a master's degree in psychology and economics from the Stockholm University.

She has been awarded the honorary degree of doctor of civil law from Bishop's University, Quebec, Canada, as well as a doctor of humane letters from Middlebury College of Vermont.

Antonia Ax:son Johnson has a net worth of US$10.2 billion, largely inherited and still growing.

The Axel Johnson Group is said to be worth in excess of US$11 billion[citation needed].