The sorption and desorption properties of four different solid adsorbents were evaluated for the trace enrichment of ibuprofen from biological samples. Chromosorb 107 gave the highest dynamic adsorption coefficient. Among the organic solvents examined, acetone gave the highest desorption coefficient. Using the Chromosorb 107 column, the optimum elution volume of the eluting solvent was evaluated from the breakthrough curve of ibuprofen. The usefulness of Chromosorb 107 as the solid adsorbent and acetone as the eluting solvent was examined for the solid-phase extraction of ibuprofen from serum in the concentration range of $20{sim}40;{mu}g/ml$.