The electrochemical behavior of propargyl alcohol (PA) on palladium electrodes in 0.1 M HClO4 was studied by differential electrochemical mass spectrometry (DEMS). Experiments with the alcohol present in the bulk of the solution have shown that the sole oxidation product is CO2. During potential cycling in the hydrogen adsorption/absorption region, C-3- (propylene and propane) and C-2- (ethane and traces of ethene/ethyne) hydrocarbons, as well as allyl alcohol, were produced. On the other hand, PA forms strongly bonded species on palladium which can be studied using a flow cell procedure. The maximum adsorption of PA was observed in the potential range 0.25-0.65 V. As for bulk studies, only CO2 was detected during the oxidation of the residues. However, some differences should be mentioned in respect of the reduction reactions: only propane, propylene and allyl alcohol were observed from the adlayer. According to these results, and taking into account the values of the charges involved in the adsorption (Q(t)) and oxidation (Q(ox)) processes, different structures were proposed for the adsorbed species. From these structures, the formation of the reduction products was justified. Results were compared with previously reported data for platinum and gold in acid media.