A procedure was developed to rate winter wheat seedlings approximately 20 days old for resistance to Cephalosporium stripe, a vascular wilt caused by the soilborne fungus Cephalosporium gramineum. Seedlings were inoculated after 12 to 15 days of growth in liquid culture in controlled-environment chambers, then assessed for disease symptoms at 7 to 8 days post-inoculation. Disease severity was assayed by measuring chlorophyll in the youngest fully expanded leaf, using a chlorophyll meter. Four replicated trials tested a total of 12 winter wheat cultivars, including both hard red cultivars from the U.S. Southern Plains and soft white winter cultivars from the U.S. Pacific Northwest. With one exception, the procedure consistently ranked cultivars correctly, according to field performance, as moderately resistant or susceptible. Jagger, a moderately resistant, hard red Kansas wheat, was ranked with susceptible cultivars in one of three trials.