The school serves the communities of Yarmouth and Dennis, and has an enrollment of approximately 900 students.

Dennis-Yarmouth, or known more commonly to the locals as "D-Y", is the second largest high school (in terms of student population) on Cape Cod, behind only Barnstable High School.

Based on data from the Massachusetts Department of Elementary and Secondary Education: As of 2021, Dennis-Yarmouth Regional High School had 881 students,[5] including 440 females, 441 males, and 0 non-binary students.

The boys team won the All-State Championship in back to back years, the only boys team in Massachusetts to have done so (the MIAA switched from a single all-state championship race for each gender in cross country to large and small school state championship races in 1990[6]) .

Harrier magazine ranked them one of the top 25 teams in the United States in 1989[7] and 1990.