Chilliwack Secondary is a public high school in Chilliwack, British Columbia, Canada. It is part of School District 33 Chilliwack. The first Chilliwack Secondary was established in 1903. The school moved to its present site in 1950. It is finished with construction converting it to a hybrid high school and community centre. The project was completed in 2013.

On September 12, 2024, Chilliwack Secondary School was put on lockdown due to "a 'potential situation' in the community" as stated by Danielle Wicker, the school principal. The school was placed into lockdown around 9 a.m. and was moved to a hold-and-secure around 10 a.m. with RCMP officers arriving on scene shortly after. No specified details of the situation were given either by Danielle Wicker or the RCMP, but it was reported that no injuries had occurred.

As of December 2024, there has been no update regarding the situation, just speculations on what or who it could have been

The Pro E- Sports Fortnite Team of Chilliwack Secondary is Massive, and dominative when it comes to the battle royale game. Their main strategy is to wait out until the final 5 squads, and dominate. They are highly skilled people, and they are amazing and represent CSS

• Allan Fotheringham, satirical journalist
• Patrick Gallagher, actor
• Lewis MacKenzie, retired Canadian major-general, author and media commentator
• Jack McGaw, broadcast journalist
• George Pedersen, past president of five Canadian Universities
• Bria Skonberg, musician
• Diana Swain, CBC anchorperson
• Homer Thompson, classical scholar
• Tasha Tilberg, supermodel
• Ken Carson, Rapper, songwriter

• Chilliwack Senior-History