Ammonia is widely used for production of many chemicals such as urea, and also as refrigerant in industrial systems. Ammonia is produced via the Haber process, in which nitrogen reacts with hydrogen in the presence of iron catalyst. The hydrogen is form by reacting natural gas and steam at high temperature. Ammonia synthesis is a reversible, thus temperature gradient occurs as the reaction progresses. The inlet temperature is usually high. To achieve this progressive temperature reduction a suitable packed bed reactor is required. A good configuration of a packed bed would help in reducing the complexities in the heat transfer equipment while ensuring a progressive reduction in temperature from the first to the fourth bed. Subsequently there is a decrease in the composition of hydrogen and nitrogen from bed to bed and a corresponding increase in ammonia conversion. This forms the bases of this design. To actualize the design, inlet operating conditions for the reactor were assumed to be 15m3/sec flow rate, pressure of 2.896 x 107Pa and temperature of 720k the diameter was calculated to be 1.5m. A gas velocity of 0.439m/s, reactor height 5.23m, mass of catalyst =14178.5kg, and volume of reactor zone/catalyst =4.051m3 were obtained.