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Fractionation of concentrated fresh sap from white birch (Betula papyrifera) yielded polysaccharide material (mainly arabinogalactan), oligosaccharides, and D-glucose and D-fructose. Separation of the oligosaccharides by a combination of charcoal column and filter paper chromatography yielded seven sugars (I–VII). These were identified as sucrose (I); 6G-fructosylsucrose (II); a F-glucosylsucrose (III); gentiobiose (IV); melibiose (V); manninotriose (VI); and verbascotetraose (VII). The small amount of sucrose found in the sap and the absence of raffinose, stachyose, and verbascose indicated that enzymic hydrolysis by a β-fructofuranosidase had occurred in the cells or vessels of the tree. The oligosaccharides are not related in either structure or composition to the polysaccharides present in the sap and wood.