H-1 nuclear magnetic resonance (H-1-NMR), C-13-NMR, and infrared spectroscopies were used to determine concentrations (c(OH), in mmol/g) of the secondary hydroxyl end groups in the low-molar-mass, OH-telechelic polybutadienes, and their hydrogenated analogs. Mean OH-functionality (f(OH) less than or equal to 2), that is, an average number of OH groups per one polymer chain, was calculated from c(OH) for each sample and each method, and the results were compared with those obtained by a conventional acetic anhydride titration method. It has been found that with molar masses of the samples studied (2310 to 3410 g/mol), the differences between individual spectrometric methods are usually not higher than approximately 10%, which corresponds to an expected relative experimental error. Certain differences in f(OH) between individual methods are discussed. No systematic change of f(OH) after virtually total hydrogenation of the olefinic double bonds of the polymeric substrate by diimide was observed.