This paper considers a manufacturer who provides two products competing on three aspects: Price，quality and service，and discusses competition equilibriums and the coordination strategy． Through formulating a simple supply chain consisting of a manufacturer and a customer，we analyze the competition results in two scenarios: The uncoordinated scenario and coordinated scenario． By a numerical simulation analysis，we discuss how competition results are influenced by the parameters． The results indicate that coordinating products decisions is a dominant strategy for a manufacturer． Coordination can bring more benefits when there is a bigger gap between the two products prices，or when the products have more advantages of quality or service cost．The coordination strategy can compensate for disadvantages of product quality cost or service cost． However，from the perspective of the whole market development，noncoordination can enhance the competitive intensity，which leads to higher product quality and service levels． Customers can benefit a lot from the noncoordination strategy，and hence the amount of customers is increasing．