Economic incentives are divided into three forms of incentive means, such as fixed wage, piece rates wage and promotion prize. Relationship between the three means is analyzed, and the notion of synthetic incentive is put forward. An enterprise should apply the three paying means synthetically to stimulate its workers to work hard. How the factors such as the level of ability, risk aversion, product error and difference of prize influence the optimum piece rates, and how these factors and the market price influencing the activities of the workers are studied. The incentive effect of pyramid-stylized wage structure and the internal mechanism that workers are divided into different kinds according to their ability level are analyzed.