At present organizations try to achieve competitive advantages using information technology (IT). Organizations not only use Information technology to manage their internal operations but also to collaborate with their customers and suppliers. For these organizations use enterprise applications. Also, organizations expect IT to address their shifting needs in on demand environment. So currently IT face challenges in integrating the various system into a function that can address the organization's on-demand needs and span over the organizational boundaries. Now Service-Oriented Architecture (SOA) imagine as an architectural framework that addresses the issues on previous enterprise applications. This paper represents the Service-Oriented Architecture in Enterprise Applications. The enterprise application gives a brief idea about enterprise applications. Afterward, this paper addresses the main problems faced by enterprise applications on the evolution of enterprise applications and the needs of service-oriented architecture in enterprise applications. Afterward, discuss Service Oriented Architecture and challenges on Service Oriented Architecture.