Removal of siloxane compounds is very important to protecting the biogas energy conversion system from decreased efficiency and parts damage. Among various siloxane removal technologies, adsorption towers are mostly used for performance and ease of operation. However, due to the difficulty of measuring the concentration of siloxane compounds in the gas stream and the complicated matrix of siloxane compounds, adsorption characteristics are not well known. In this study, the adsorption characteristics for multi siloxane components are experimentally studied. Four siloxane components are vaporized in the nitrogen stream supplied continuously to a lab-scale adsorption tank with commercially available silica gel or activated carbon and an FTIR (Fourier-transform infrared spectroscopy) analyzer was used for the online siloxane analysis to find out the adsorption characteristics. While a mixture of L2, L5, D4 and D5 adsorption capacity of silica gel and activated carbon are similar -11.13 and 11.56wt% respectively-adsorption characteristics of each adsorbent was well distinguished in terms of breakthrough behavior. Silica gel shows sequential breakthrough for each siloxane compound and a more noticeable unique time range for Rc > 1, while relatively simultaneous breakthrough was shown for activated carbon adsorbents.