In the modern era, power dissipation has become a major and vital constraint in electronic industry. Many techniques were already introduced to reduce power dissipation. Gate Diffusion Input (GDI) technique allows power dissipation to a greater extend compared to the other logic styles. This paper also reduces the transistor count and thus the area of the circuit. Thus, the circuit will be much simpler and easy to manage. This paper describes the design of an 8-bit arithmetic logic unit using GDI technique and also the comparison with other logic styles.