Pokeweed antiviral protein from seeds (PAP-S) is a ribosome inactivating protein which has lowest toxicity and highest inhibition activity as opposed to other pokeweed antiviral proteins and its three potential glycosylation sites (10, 44, 255) were shown to bind to N-acetylglucosamine. Good quality crystals of PAP-S were grown at high protein concentration (100 mg ml-1) and high temperature (306 K). The crystals have space group I222 and cell parameters a = 78.7, b = 85.2 and c = 93.0 A. An X-ray diffraction data set with resolution up to 1.8 A was collected. This high-resolution data will help to locate the sugars bound to the protein and provide accurate structural data for understanding structure-function relationships of PAP-S.