Pterostylis decurva, commonly known as the summer greenhood, is a species of orchid endemic to south-eastern Australia. As with similar greenhoods, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves but the flowering plants have a single flower with leaves on the flowering spike. This greenhood usually flowers in summer and has a white flower with green stripes and a brownish tinge. It is similar to P. aestiva but has paler green flowers.