The present invention provides a method for purifying butyrylcholinesterase from various biological fluids. Biological fluids include, e.g., blood, blood fractions, plasma, and bioreactor broths, and other such mixtures containing butyrylcholinesterase. In one embodiment, the invention provides a method for the production of purified, virally inactivated butyrylcholinesterase by contacting a biological fluid containing butyrylcholinesterase with a cationic exchange chromatography material, with an affinity chromatography material, and treating the fluid with solvent detergent. The resulting purified butyrylcholinesterase can also be subjected to a pasteurization step, and formulated in a sodium chloride/sodium phosphate solution for storage or lyophilization.