St. John on Patmos is an oil on panel painting by the Netherlandish artist Hieronymus Bosch, created c. 1489.

[1] The reverse is also painted, the title of that picture is Scenes from the Passion of Christ and the Pelican with Her Young.

It was noted in the 1940s that the two paintings may have been designed as wings of an altarpiece.

Such an origin would explain the grisaille painting on the reverse, as it is characteristic of polyptychs to have both sides of folding panels decorated.

It has since been suggested that the altarpiece in question was an artwork which is known to have been made for St. John's Cathedral, 's-Hertogenbosch.