Numerical methods are powerful problem-solving tools, Techniques of these methods are capable of handing large system of equation, some problem in physics and engineering which are impossible to be solved analytically. The main object in this thesis is to study and reformulate some numerical methods for solving system of retarded delay differential equations. We get good results in each presented methods for solving system of retarded delay differential equations. This is done by writing a computer Maple program version 13. For the purpose of comparison we compared exact results with approximate solution which is obtained by the above methods.