2020–21 Duke Blue Devils men's basketball team

The 2020–21 Duke Blue Devils men's basketball team represented Duke University during the United States2020–21 NCAA Division I men's basketball season. They were coached by 41st-year head coach, Mike Krzyzewski. The Blue Devils played their home games at Cameron Indoor Stadium in Durham, North Carolina, as a member of the Atlantic Coast Conference.

Known for consistent high-level performance under Krzyzewski's tenure, the Blue Devils struggled to match their norm this season. Duke fell out of the AP and Coaches Poll rankings within the first few weeks and struggled to maintain a winning record. The Blue Devils finished the 2020–21 season 13–11, and 9–9 to finish in tenth place in ACC play. Duke spent much of the late season on the bubble, according to bracketologists, and ultimately their season ended when a positive COVID-19 test forced them to drop out of the ACC tournament ahead of the quarterfinals. Duke missed the NCAA tournament for the first time since 1995.