Software Engineering is evolving every day. New Technologies are being introduced. For fast and easy development several new methodologies are introduced. In this paper we will focus on two approaches which are Component Based Software Engineering [CBSE] and Object Oriented Software Engineering [OOSE]. CBSE focuses on development of software with the help of reusable components and how CBSE does the reuse of grained components and plans to deliver better quality and output. Whereas, the OOSE is used in software design in object-oriented programming. This model includes all phases of requirements, analysis, design, implementation and a testing model. Moreover, here we conclude the difference between the two approaches.