Objectives : DaeBangPungTang(DBPT) is one of the prescriptions used for the treatment of knee arthritis in oriental medicine. The present study aimed to examine the analgesic effect of DBPT on a rat model of carrageenan-induced arthritis, and the relations between DBPT-induced analgesia and endogenous nitric oxide(NO) and inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and c-Fos protein expression in the spinal cord. Methods : Carrageenan-induced arthritis rat model was used to test the effect of DBPT as a chronic pain model. After the induction of arthritis, rats subsequently showed a reduced stepping force of the affected limb for at least tile next 4 days. The reduced stepping force of the limb was presumably due to a painful knee, since oral infection of indomethacin produced temporary improvement of weight bearing. DBPT dissolved in normal saline was minted several acupoints. After the treatment, behavioral tests measuring stepping force were periodically conducted during the next 12 hours. Results : DBPT produced significant improvement of stepping force of the hindlimb affected by the arthritis lasting at least 9 hours. The magnitude of this improvement was equivalent to that obtained after an oral injection of 3mg/kg of indomethacin and this improvement of stepping force was interpreted as an analgesic effect. DBPT produced the improvement of stepping force of the affected hindlimb in a dose-dependent manner. Both NO production and iNOS, COX-2 protein expression increased by arthritis were suppressed by DBPT. DBPT on combination with electroacupuncture (EA) produced more powerful and longer lasting improvement of stepping force of the hindlimb affected by the arthritis than either DBPT or EA did. Conclusion : The present study suggest that DBPT produces a potent analgesic effect on the chronic hee arthritis pain model in the rat and that DBPT-induced analgesia modulate endogenous NO through the suppression of iNOS/COX-2 protein expression.