The　Co/Mg/Al　catalysts　were　prepared　from　the　hydrotalcite-like　compounds　containing　Co,　Mg　and　Al,　and　applied　to　the　steam　gasification　of　biomass.　It　is　found　that　the　Co/Mg/Al　(10/40/50)　catalyst　exhibited　much　higher　activity　and　resistance　to　coke　deposition　than　Co/alpha-Al2O3,　Co/Al,　Co/Mg　and　Ni/Mg/Al　(9/66/25)　catalysts.　The　catalyst　characterization　using　BET,　TPR,　TPO,　XRD,　H-2　adsorption,　and　TEM　indicates　that　the　Co/Mg/Al　(10/40/50)　catalyst　after　the　reduction　has　a　nanocomposite　structure　of　Co　metal　particles　(similar　to　14　nm)　and　oxide　particles　(similar　to　16　nm)　of　MgAl2O4-based　solid　solution.　On　the　other　hand,　according　to　the　catalyst　characterization　after　the　catalytic　use　and　regeneration,　the　structural　change　of　MgAl2O4-based　solid　solution　to　MgO-based　solid　solution　can　be　a　cause　of　the　decrease　of　the　catalytic　activity.　(C)　2013　Elsevier　B.V.　All　rights　reserved.