A zeolite adsorbent for desulfurization and a method of preparing the same. More particularly, a zeolite adsorbent for desulfurization in which the relative crystallinity of Y zeolite that is ion exchanged with Ag is 45% to 98%, and a method of preparing the same. The zeolite adsorbent for desulfurization has excellent crystallinity over the known zeolite adsorbent for desulfurization, and thus has better performance of adsorbing sulfur compounds though it contains less Ag. Accordingly, when the sulfur compounds of a fuel gas are removed by employing the zeolite adsorbent for desulfurization, a desulfurizing device that is bettereven with less cost can be constructed.