Abstract: A surgical retractor assembly includes a support post having a lower portion and an upper portion, with the lower portion having an adjustable clamp for attaching the post to a rail provided on a surgical operating table. This clamp is capable of attachment to the rail over a flexible surgical drape. A screw mechanism is associated with the clamp so that the clamp can be attached and adjusted by the operator in an area above the rail on the surgical table. An extension rod is adjustably connected to the post and is adapted to extend in a direction generally over a patient on the operating table. A rigid ring member is connected to the extension rod for positioning a plurality of retractor blades for use on a patient. At least one retractor blade is mounted on the ring member.