Disclosed are an apparatus and a method for removing halogens generated during the preparation of polybutene, which are capable of improving the utilization of polybutene and light polymers by removing halogen components contained in the polybutene and the light polymers. The method for removing halogens generated during the preparation of polybutene comprises the steps of: preparing a reaction product by supplying a catalyst and a reaction raw material to a reactor and polymerizing; removing a catalyst component from the reaction product and neutralizing; separating the reaction product into an organic compound and impurities comprising the catalyst component; heating the organic compound to distill an unreacted material; and removing a halogen component in a remaining polymerization mixture after the distillation using a halogen removing catalyst, or removing a halogen component in polybutene and light polymers obtained from the polymerization mixture using the halogen removing catalyst.