Police were called to Freeman High School, in Rockford, Spokane County at about 10.30am local time.
Spokane County Sheriff's Office confirmed there had been a shooting at the school.
Sheriff Ozzie Knezovich said six people had been shot and one person had died as a result of their wounds.
City of Spokane Fire Chief Brian Schaeffer said the fatality was a male student.
At least three people have been admitted to the Providence Sacred Heart Medical Center.
Their ages and extent of their injuries are not currently known.