The index, which covers business conditions in the industrial belt of Indiana, Illinois and Michigan, rose by 1.2 points to 56.8 pushed by gains in new orders, order backlogs and supply deliveries.
Production and employment also expanded, but at a slower pace than January, the report said.
The production index slipped from 60.9 to 60.2, remaining above 50, which is the break even point between contraction and growth.
The new orders index rose from 58.2 to 60.2 The employment index, marking the number of employees, fell from 58 to 55.7.
The report, which is produced by the Institute of Supply Management-Chicago Inc. and Deutsche Borse AG, noted a drop from 50.3 to 49.9 in supplier deliveries, while the index for inventories in the region dropped from 55 to 50.1.