The church in the village of Buchberg Seewalchen dates from the 16th century.
The church has one nave, pilaster, cross vaults and stucco frames at the choir termination date from the period of 1720-30. The altar with baroque pieces (from the parish church Seewalchen) and the image of the Holy Trinity dates back to 1700.
Around 1892, parts of the parish church Seewalchen, which was being restored at that time, were incorporated in Buchberg. In 1893, a statue of St. Stephen was added to the new altar.
Roof, tower and facade were renovated in 1978 and 1979. This involved approximately 2000 hours of voluntary work, the wood for the tower and roof construction was donated.
Another renovation took place in 1998.
As of 1929, masses were held in the summer. Today, the church is used for masses and devotions on special occasions.