Herein, we fabricate cuprous oxides within the pores of zeolite Y by the ion exchange and liquid reduction (LR) strategy combined with the confined effect of micropores. First, Cu²⁺ ions are incorporated into the pores of zeolite Y through ion exchange, and then part of Cu²⁺ ions within the pores of zeolite Y are reduced to cuprous oxide by using sodium borohydride as reducing agent. As-fabricated cuprous oxides within the confined pore of zeolite Y (Cu(I)–Y) adsorbent exhibits excellent adsorption desulfurization performance such as large breakthrough adsorption sulfur capacity of DBT (20.0 mg S g⁻¹) and superior regeneration (15 cycles). The outstanding adsorption desulfurization performance could be attributed to the unique pore structure, proper pore sizes and π-complexation interaction between Cu(I) sites and aromatic sulfur compounds such as DBT and TP. Besides, the confined effect of pore for Cu(I)–Y also plays an important role in stabilizing Cu(I) sites in the micropores. This facile fabrication strategy combined with the size and confined effect of micropore for Cu(I)-zeolite adsorbent provides a new way for the composite of porous materials with various active sites.