The liquid-phase oligomerization of 1- hexene ( at 200 degrees C and 50 bar) was studied using, as catalysts, templated sol- gel aluminosilicates Al- MTS prepared in an acid medium with different Si/ Al atomic ratios ( 7.5- 110). The acid sites of the Al- MTS catalysts were analyzed using ammonia temperature programmed desorption ( TPD), 27Al magic angle spinning nuclear magnetic resonance ( MAS NMR), and P-31 MAS NMR of the adsorbed triethylphosphine oxide ( TEPO). High oligomerization conversions were always achieved ( 70%80%) with an enhancement of the selectivity toward heavier hydrocarbons with decreasing Si/ Al, along with a low cracking selectivity ( C-3- C-5 < 6%). The study of the influence of the main operation variables on the performance over a standard Al- MTS sample ( Si/ Al) 30) indicates that an increase of the temperature ( 120-200 degrees C) led to higher selectivities toward heavier hydrocarbons, whereas the opposite trend was appreciated with the weight hourly space velocity ( WHSV) ( 0.40-1.26 h(-1)).