Glucagon-like peptide-1 (GLP-1) analogs, widely used for the treatment of obesity and type 2 diabetes, are typically administered subcutaneously. Although oral formulations could improve patient adherence, their development is limited by enzymatic degradation in the gastrointestinal tract and poor intestinal permeability, resulting in low oral bioavailability. To overcome these limitations, this study developed a zinc oxide (ZnO) microparticle–based oral delivery platform and evaluated the delivery performance of liraglutide and semaglutide using two ZnO morphologies: glochid particle (GP) and sphere (SP). Physical adsorption was first applied to evaluate encapsulation efficiency (EE) and loading efficiency (LE), allowing optimization of peptide selection and adsorption conditions. To further enhance peptide binding, hydrophobic interaction–mediated adsorption using an adsorption enhancer (AE) was introduced, and the optimal AE was identified using the same quantitative criteria. The structural integrity and physicochemical properties of the peptide–ZnO complexes were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and circular dichroism (CD). In vitro release studies showed that ZnO-adsorbed liraglutide exhibited a more sustained and controlled release profile compared with the free drug. Ex vivo studies using porcine intestinal tissue revealed morphology-dependent penetration, where GP reached the epithelial layer and demonstrated greater tissue access than SP. Furthermore, in vitro permeability studies under GI-mimicking conditions indicated that GP exhibited stronger mucoadhesion and significantly enhanced peptide permeability. Overall, ZnO-based adsorption strategies improved peptide loading, structural stability, mucosal interaction, and intestinal permeability. These findings suggest that ZnO microparticles are a promising oral delivery platform for GLP-1 analogs and other peptide therapeutics.