The price equilibrium between oligopoly service providers in service networks with congestions was studied.The bilevel MPEC model of service competition in service networks was described.The lower level is Wardrop equilibrium between customers,while the upper level is the Nash equilibrium between service providers.The existence of the price oligopoly equilibrium was proved and its properties were analysed.The practice in the express service industry in China was discussed.A numerical example was given to show that service providers should take the customer preference into consideration when making decisions.