Background: If the weakness of the knee muscles persists and there is pain at the same time, lumbar mobilization can be used. Objectives: This study investigated the immediate effect of lumbar joint mobilization on postural sway and knee pain in elite volleyball players. Design: Randomized controlled trial. Methods: Twelve male elite volleyball players were recruited for this study. Lumbar joint mobilization was performed in all study subjects. Evaluation items were static and dynamic balance and knee pain change. All evaluations were made immediately after the intervention. Results: C90 area, trace length, and STD Y deviation in the open static balance were significantly decreased after intervention (P<.05). C90 area, trace length, Velocity, STD X deviation, and STD Y deviation in static balance with closed eyes decreased significantly after intervention (P<.05). In dynamic balance, the left and right side. COPs were significantly increased. Pain significantly decreased after intervention (P<.05). Conclusion: This study found that lumbar joint mobilization is an effective method for improving postural sway and knee pain in elite volleyball players.