Stjärnholm, Manor house in Oxelösund Municipality, Sweden

Stjärnholm is a manor house in Oxelösund Municipality with a church, modern chapel, and extensive parklands along the Swedish coastline. The complex blends historic buildings with contemporary facilities and offers different types of accommodations from private rooms to dormitory-style spaces.

Stjärnholm traces back to the Nygård farm, first mentioned in 1381. In 1638 the estate was formed when Jöns Månsson Silfverstierna bought Nygård from the crown together with Sunda, Vivesta and Väster-Aspa. The stone church was built in 1671 as a private chapel, and the present main building replaced a wooden one in 1735–1748. During the Russian raids of 1719 the estate was plundered but its buildings were not burned.

The name Stjärnholm was not used by founder Jöns Månsson Silfverstierna, who called the estate Nygård; it appeared during his son-in-law's time. The estate church, built in 1671 as a private chapel, never became its own parish: the mother parish of Sankt Nikolai protested, and a settlement was reached only in 1750. No churchyard was laid out; an old sailors' burial ground at Gamla Oxelösund was used instead.

Stjärnholm lies in Oxelösund Municipality in Södermanland, near the Baltic coast south of Stockholm. The estate is a diocesan retreat centre of the Strängnäs diocese, so buildings and grounds may be reserved for courses and groups; check access before travelling. The 1671 chapel and the 1735–1748 main building stand close together, with the linden avenues planted in front of the manor.

The estate's oldest surviving building is the grain magazine, said to date from the time of Wilhelm Böös Drakenhielm in the 1670s. His stone barn, built on piles in what was then marshy ground, now serves as a riding school. The copper roof of the 17th-century main building was later sold off by Peter Körning when he fell into debt.