The index reading was the highest since August 2004.
The Institute for Supply Management (ISM) said its index of national factory activity rose to 58.4 in January from 54.9 in December. The median forecast of 79 economists surveyed by Reuters was for a reading of 55.5.
A reading below 50 indicates contraction in the manufacturing sector, while a number above 50 means expansion.
(Reporting by Ellen Freilich Editing by Padraic Cassidy)