Over the last 20 years, China's demand for and supply of livestock products has increased dramatically. Although, China's livestock production has changed, with the share of pork production declining, pork production remains the core of the country's livestock industry. China's hog industry is adjusting to capture the benefits of specialization. This paper attempts to capture structural changes in China's hog production, its evolving trends, and economic efficiency. We estimate parametrically the overall efficiency and scale elasticity of 2500 surveyed hog farms in China. Our analysis indicates that the large commercialized farms are the most efficient but the middle size specialized farms with increasing returns to scale production technology are the most profitable.