We studied the capacity of an API-rHBsAg purification process to eliminate DNA contamination from yeast-host cell. Firstly, was demonstrated consistency of manufacturing purification process to remove DNA, from (3.9 ± 1.9)10⁸ pg/dose in starting material to (3.4 ± 1.6) pg/dose, equivalent to 8.2 log in Active Pharmaceutical Ingredient (API), measuring DNA quantity in several unit operations along manufacturing process for twenty batches, five consecutive in 2000, 2001, 2003 y 2005. These values for API, lower than 10 pg/dose, accomplish current WHO requirements for Hepatitis B vaccines obtaining by recombinant DNA technology (WHO, 1989; European Pharmacopoeia, 2001a). The main removal factor for manufacturing process, equivalent to 6.4-log, was reached in negative anion-exchange chromatography. Then, the capacity of immunoaffinity chromatography and positive anion-exchange chromatography to remove chromosomal DNA purified from yeast-host cell was assessed using a scaled-down chromatographic process which was shown to yield product meeting purity criteria set for the manufacturing process. Log₁₀ reductions for DNA through the immunoaffinity chromatography and positive anion-exchange chromatography were 7.3 ± 0.1, and 5.8 ± 0.1 respectively. Overall, these studies indicate that total DNA clearance factor for API-rHBsAg manufacturing process was 19.4 log, 2.4 times higher than the real DNA contamination, indicating that API-rHBsAg manufacturing as described here have sufficient DNA reducing capacity to achieved a high margin of DNA safety.