The molar mass distributions of various polyvinylalcohol (PVA) samples having molar masses ranging from 14 to 610 kg mol(-1) have been determined by size exclusion chromatography (s.e.c.) using dimethylsulfoxide (DMSO) as the eluent. Four sets of columns were tested. The best results were obtained with two Ultrahydrogel columns (Waters). Calibration was performed using seven polyethyleneoxide (PEG) samples having known molar masses and narrow molar mass distributions. The PEO calibration curve was transformed to a PVA calibration curve by application of a broad standard calibration procedure. The validity and reliability of the new method was verified by a comparison of the M-w and [eta] calculated from the molar mass distribution and the values determined by independent off-line light-scattering and Ubbelohde viscometry. The data are in very good agreement even up to very high molar masses of 610 kg mol(-1).