Abstract: A bilayer combination tablet for oral administration, which is prescribed for alleviation of symptoms or signs of osteoarthritis (degenerative arthritis), alleviation of symptoms or sings of rheumatoid arthritis, alleviation of symptoms or signs of ankylosing spondylitis, alleviation of acute pain in adults (post-operative or post-tooth extraction pain), alleviation of primary dysmenorrhea, or alleviation of severe and moderate acute or chronic pain. The bilayer combination tablet includes: a controlled-release layer containing tramadol as an active ingredient; and an immediate-release layer containing celecoxib as an active ingredient. A composition for treating pain may be provided, which has a long-lasting analgesic effect for 12 hours while reducing the side effects of tramadol by slow release of water-soluble tramadol and immediate release of poorly soluble celecoxib.