University spokeswoman Julie Peterson said some potential applicants may have mistakenly thought the court's June 2003 ruling completely abolished affirmative action in admissions. Instead, the ruling required the school to modify the way it accounts for race in undergraduate admissions.
Among the school's 6,040 new first-year students, 350 were black, compared with 410 last year. Applications from black students were down more than 25 percent, officials said.
President Mary Sue Coleman said the numbers are reason for concern.
"We are closely monitoring our admissions recruiting activities this year to make sure we are doing all we possibly can to encourage all qualified students to apply," she said.
The figures include students who entered in spring, summer, or fall of 2004.
Last year, the Supreme Court upheld a general affirmative action policy at the University of Michigan law school but struck down the university's undergraduate formula as too rigid because it awarded admission points based on race. In response, the university adopted an application that considers race but does not award points. It includes new short-answer questions and an optional essay.