This research optimized the biosorption of Cd (II) and Pb (II) in Olea europea endocarp, evaluating factors such as particle size, pH, acid or basic pretreatment and initial concentration of both metals. A Batch type agitation system was used where it was determined that the time in which the removal of both metals reached equilibrium was 40 minutes. The factorial design resulted in a suitable particle size for the biosorption process of 75-150 μm and a basic pretreatment with NaOH, the latter being the most important factor in the removal of both metals. Optimization by the Method Surface Response (MSR) resulted that pH=6.1 and initial concentration of 88.3 mg/L are the optimum conditions to achieve maximum removals of 28.1 and 58.5 mg/L for Cd (II) and Pb (II) respectively. It was also found that Olea europea removes more of each metal in monometallic solutions than in bimetallic solutions.