We aimed to unravel the clinical benefits and the plausible underlying psychophysiological mechanism based on available randomized controlled trials (RCTs). Meta-analysis of 26 RCTs shortlisted from electronic databases from 1997 to 2006 shows that qigong had some effects on increasing the numbers of white blood cells and lymphocytes, stroke volume, peak early transmitral filling velocity, peak late transmitral filling velocity, forced vital capacity, and forced expiratory volume, and, conversely, lowering of total cholesterol, systolic blood pressure, diastolic blood pressure, and depressive mood scores. Explanatory pathways may pertain to stress reduction via nervous, endocrine, and immune systems. Limitations on methodology are discussed and directions for further studies are suggested. Because of its safety, minimal cost, and clinical benefit, health qigong can be advocated as an adjunctive exercise therapy for older people with chronic conditions.