A technique for examining frictional effects at a sample/platen interface during uniaxial compression, developed for metals, has been applied to viscoelastic gels and doughs. Flat, ring‐shaped samples of gelatin and wheat starch gels and of a hard wheat flour dough are prepared with an internal ring diameter ofDi.These viscoelastic materials show, in uniaxial compression, the same qualitative behavior as that reported by Male and Cockcroft for metals (J. Institute of Metals,93, 38–46, 1964). When the sample/platen interface is lubricated, that is, when the interfacial friction is low,Diincreases as the deformation increases; when the friction at the interface is high,Didecreases with increasing deformation. With the viscoelastic fluid (dough) the central hole of the ring always closes up at high enough deformations even when the platen/sample interface is initially lubricated except when lubricated Teflon platen surfaces are employed. To a greater extent than observed for metals, the effective frictional coefficient at the gel or dough interface seems sensitive to extent of deformation.