Based on the model of monopsony，this article explores the effect of minimum wages on labor in the developing countries in which the economy is developing rapidly.We take the Yangtze River Delta region as an example to analyze the employment effect of minimum wages on workers.The empirical study of statistical data from China Industry Business Performance Data demonstrates that the increase of minimum wages could contribute to employment of workers in Shanghai and Zhejiang where there is a lower ratio of the minimum wage to the urban average wages，but hinders the employment of workers in Jiangsu where there is a higher ratio of minimum wages to the urban average wages.We also find that the increase of minimum wages in Shanghai could create more jobs than in Zhejiang.In addition，the rise in the minimum wage has a major impact on small businesses and private enterprises.