The oligomerization of biomass-derived light olefins offers a promising potential for the synthesis of sustainable jet-fuels, which mostly comprise C₁₀-C₁₈ hydrocarbons. However, the selectivity control of oligomerization reaction remains a challenge. In this contribution, oligomerization of pentene and hexene mixtures was studied over acidic mesoporous Al–SBA–15 catalyst in continuous operation, and the impact of different process parameters on conversion and selectivity is thoroughly evaluated. Kinetics evaluation showed that the reactivity of pentene is higher than that of hexene. Selectivity to jet-fuel range products >98% were achievable at low-to-moderate conversions (<50%), while higher conversions (ca. 90%) resulted in selectivities of ca. 75%. Notably, the product distribution at iso-conversion was unaffected by temperature, pressure, and weight hourly space velocity, implicating that adjusting the conversion is the primary way to tune the selectivity of the Al-SBA-15 catalyst. This understanding of the oligomerization process opens the door for the research devoted on the oligomerization of complex olefin mixtures, mimicking the process stream of olefins production units, in order to achieve “biomass to jet-fuel” transformation.