An auto-locking surgical retractor assembly has a retractor frame with a number of adjustable arms. Each adjustable arm has a U-shaped recess for removably engaging the post of a retractor blade. A spring-loaded locking pin protrudes slightly from the arm into the U-shaped recess to hold the post of retractor blade in place. The locking pin is temporarily retracted by insertion of the retractor blade post into the U-shaped recess, but subsequently extends to lock the retractor blade post in place. The user must exert sufficient force on the retractor blade to temporarily depress the spring-loaded locking pin in order to remove the retractor blade post from the U-shaped recess.
