Controlling internal or superficial bacterial contamination from sweet potato in vitro cultures can be difficult. Contaminants are not easy to detect visually, and most methods reported for bacteria elimination recommend the use of several antibiotics. Intensive use of these chemicals results toxic to the plants and frequently generates resistant strains. At the International Potato Center (CIP), a large sweetpotato in vitro collection is held (5,499),and bacterial contaminants have been detected in the collection. Several treatments applying antibiotics alone or in combination with meristem/shoot tip culture have been tested. The majority of these methods were unsuccessful. Currently, about 200 sweetpotato clones per year are cleaned from bacteria using a method based on reducing or eliminating the contaminant by transferring the plants to soil and re-introducing to in vitro culture.