In this study, the adsorption behavior of diclofenac (DCF) was investigated using moringa oleifera (MO) as a biosorbent. The pH dependence, kinetic parameters, and surface-charge interactions were studied to understand the adsorption mechanism. The results demonstrate that MO exhibits a positive surface charge at low pH values (<6) and a negative charge at higher pH values (>6), indicating electrostatic interactions with negatively charged DCF. Kinetic study revealed a significant removal percentage of approximately 75% within 90 min, suggesting the potential of MO as an effective adsorbent. The pH dependence of DCF adsorption was evident, with the highest removal observed at pH 2 and the lowest at pH 8. This study highlights the potential of MO as a promising biosorbent for DCF removal and emphasizes the need for further investigations to optimize the adsorption process and explore its wider applications in pharmaceutical removal.