Yordanos Mesfin,Kumela Desale,Isso Mohammed,2024-04-022024-04-022023-06http://10.194.1.109:8080/xmlui/handle/123456789/879This project contains three chapters, with basic definitions, solving and applications of complex differen tiation. Chapter one is about preliminary concepts. It contains complex number, complex conjugates, limit, continuity and rule of differentiation. Chapter two deals with complex differentiation. This chapter includes derivative, Cauchy-Riemann equations, analytic function and harmonic function. The last chapter is about application of complex differentiation. Finally, this paper contains the general conclusion and reference.enThesis