Jacobus Jansenius, alternatively Jansonius or Janssoon (1547–1625) was a Dutch theologian who served as rector of Leuven University.
In 1580 he became an ordinary professor of Theology and a canon of St. Peter's Church, Leuven.
In 1589 he was appointed president of Pope's College and rector of the university.
On 29 November 1598 he succeeded Thomas Stapleton as Regius Professor of Sacred Scripture.
[1] Jansenius died on 30 July 1625 and was buried in Pope's College chapel.