Stanislaus was born on October 28, 1550, to Margaret and John Kostka, on the estate in Rostkov, Poland. Both parents came from the nobility: those considered as the "first families" of Poland, and John was a senator. They were known to keep their children "from all luxury and self-indulgence."
When Stanislaus was fourteen, he and his brother were sent to the Jesuits' college in Vienna. Stanislaus was known to have "a serious and quiet nature." He dressed plainly, did not mingle unnecessarily with visitors, and spent a great deal of time in prayer. He was described as being "innocent but not ignorant." Stanislaus' life style and values did not set well with his older and more-worldly brother Paul, who abused the younger brother physically and verbally.
When Stanislaus was sixteen, he asked to be admitted to the Society of Jesus, but his father refused permission, and the Jesuit provincial in Poland could not receive him without that permission. Stanislaus then walked 450 miles to the Jesuit Provincial of Germany [Saint] Peter Canisius, who had the young nobleman sweep floors and help in the kitchen. To avoid Senator Kostka's wrath, Canisius sent Stanislaus to Rome with two Jesuits. There, after walking over 1200 miles in three months, the young man met the Father General, Francis Borgia.
Stanislaus spent some time at the Jesuit house adjacent to the Church of the Gesù, then some time at the Roman College before beginning the novitiate. His behavior as a novice is described as a "smiling, happy service of God." However, in those ten months, his health declined rapidly, and on the feast of the Assumption, August 15, 1568, Stanislaus died.
The remains of Stanislaus Kostka are venerated in the Jesuit church of Sant'Andrea al Quirinale, in Rome. He was canonized on December 31, 1726.