The Tri-County Conference is an affiliation of several small high schools in central Illinois. Current membership includes

• Putnam County High School
  Putnam County High School
  Putnam County High School is a public high school located at 402 East Silverspoon, Granville, Illinois. Its mascot is the Panthers, and its teams play in the Tri-County Conference....
  
  
• Midland High School
  Midland High School (Illinois)
  Midland High School, also known as Varna Midland, or MHS, is a public four-year high school located at 1830 Illinois State Route 17 outside of Varna, Illinois, a village in Marshall County, Illinois, in the Midwestern United States. MHS serves the communities of Varna, Lacon, and Sparland...
  
  
• Henry-Senachwine High School
  Henry-Senachwine High School
  Henry-Senachwine High School, or HSHS, is a public four-year high school located at 1023 College Street in Henry, Illinois, a village in Marshall County, Illinois, in the Midwestern United States. HSHS serves the communities of Henry and Putnam...
  
  
• Marquette High School
  Marquette High School (Ottawa, Illinois)
  Marquette Academy is a private, Roman Catholic high school in Ottawa, Illinois. It is located in the Roman Catholic Diocese of Peoria.-History:...
  
  
• Roanoke-Benson High School
  Roanoke-Benson High School
  Roanoke-Benson High School is a comprehensive high school located at 208 West High Street, in Roanoke, Illinois. The school is a member of the Tri-County Conference, and compete under the name Rockets....
  
  
• Low Point-Washburn High School
  Low Point-Washburn High School
  Low Point-Washburn Junior/Senior High School is a public junior-senior high school in Washburn, Woodford County, Illinois. It handles seventh through twelfth grade and is in the same building as the Lowpoint-Washburn Community Unit School District 21 offices and Lowpoint-Washburn Middle School ...
  
  
• Woodland High School
  Woodland High School (Illinois)
  Woodland High School is a small public high school located at 5800 E 3000 North Rd., in Streator, Illinois. Its athletic teams play in the Tri-County Conference; its mascot is the Warriors....
  
  
• DePue High School
  DePue High School
  DePue High School, or DHS, is a public four-year high school located at 204 Pleasant Street in De Pue, Illinois, a village in Bureau County, Illinois, in the Midwestern United States. DHS serves the communitu and surrounding area of DePue...
  
  

New members

For the 2011-12 school years, the following schools will be joining the Tri-County Conference:

• Hall Township
  Hall High School (Illinois)
  Hall High School, also known as Spring Valley Hall, or HHS, is a public four-year high school located at 800 West Erie Street in Spring Valley, Illinois, a small city in Bureau County, Illinois, in the Midwestern United States. HHS serves the communities and surrounding areas of Spring Valley,...
  
  

Hall Township is leaving the dissolving NCIC after seven decades as that conference's smallest member school; upon joining the Tri-County, Hall's population of 443 will make it the largest school in that conference.