Osteoarthritis (OA) is a costly disease that causes much morbidity and mortality in the world, and it was the sixth leading cause of disability in developed countries. We aim to study the utilization pattern of alternative therapies and their effects on quality of life and personal health spending in Chinese OA patients in Hong Kong. Five-hundred forty-seven patients with OA from four regional hospitals in Hong Kong were recruited, and we measured various types of alternative therapies, SF-36 scales, an overall Health Utility Index derived from a pre-scored multi-attribute classification system based upon SF-36 health surveys, health spending per person and out-of-pocket payments and side-effects. The study shows that out of the 547 OA patients, the patients have used a wide spectrum of alternative therapies and often used a multiplicity of them. Payment for alternative therapies constitutes 5% of the overall personal healthcare spending, and 29% of the out-of-pocket payments. The use of alternative therapies was significantly associated with higher personal healthcare spending (p = 0.01), after adjusting for socioeconomic variables, years of OA and severity of OA. The use of alternative therapies was not significantly associated with an improvement in the quality of life in the regression analysis (p = 0.64). The use of alternative therapies was statistically significant associated with the side effects, including gastric discomfort and gastric ulcer/bleeding (p = 0.04, 0.02, respectively). Alternative therapies were used extensively by OA patients in Hong Kong. Clinicians, health policy makers, and insurance carriers should be aware of the potential health and economic effects in practice and policy formulation.