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Efficient production of fuels and chemicals from lignocellulosic biomass is the main goal of biorefinery processes. Herein, the metal-modified heteropolyacids with tunable Lewis and Brønsted acid sites were designed as the monolithic multifunctional catalyst for valorizing cellulose and lignocellulosic biomass to alkyl levulinate, a versatile platform molecule. Among them, Al-exchanged two protons of H 4 SiW 12 O 40 (Al 2/3 H 2 SiW 12 O 40) was found to be uniquely effective. The kinetic behavior describing the conversion of cellulose to ethyl levulinate was investigated to monitor the process, and compared between parent H 4 SiW 12 O 40 and Al 2/3 H 2 SiW 12 O 40 to understand the mechanistic role of Al3+. The introduction of Al3+ substantially facilitated cellulose depolymerization and glucose-to-fructose isomerization, leading to a high rate and product selectivity. The estimated activation energies for cellulose degradation and glucopyraoside alcoholysis decreased by 50.6 kJ/mol and 40.9 kJ/mol, respectively. 50–72% yields of ethyl levulinate were accomplished from cellulosic biomasses such as pine wood, eucalyptus, bamboo, bagasse and Napier grass. Al 2/3 H 2 SiW 12 O 40 allowed cellulose conversion in various linear alcohols producing high-yield alkyl levulinate, and could be reused multiple times with a good stability. This study opens a reliable and promising avenue for one-pot transformation of cellulose and raw lignocellulosic biomass to ester compounds. Unlabelled Image • An Al-modified H 4 SiW 12 O 40 (AlHSiW) was designed for valorizing cellulosic biomass. • AlHSiW facilitated cellulose depolymerization and glucose-to-fructose isomerization. • Activation energy for cellulose degradation and glucoside conversion both decreased. • High reaction rate and product selectivity were accomplished from cellulosic biomass. • AlHSiW is a reliable candidate as multifunctional, efficient and recyclable catalyst. [ABSTRACT FROM AUTHOR]