The power system analysis and design is generally done by using power flow analysis .This analysis is carried out at the state of planning, operation, control and economic scheduling .they are useful in determining the magnitude and phase angle of load buses, and active and reactive power flows over transmission lines, and active and reactive powers that are injected at the buses. For this work the gauss-seidel method is used for numerical analysis. The objective of this project is to develop a MATLAB program to calculate voltages, active and reactive power at each bus for IEEE 14 bus systems. At first IEEE 5 bus system is calculated by using hand calculations and compared with MATLAB Program results and then IEEE 14 bus system MATLAB program is executed with the input data. This type of analysis is useful for solving the power flow problem in different power systems which will useful to calculate the unknown quantities.