Abstarct: Designing the casing pipe of a well is of great importance in drilling engineering because it is sensitive in terms of safety and may carry high costs. Nowadays, a commonly method is used which is called the maximum imposed load method. mextal destruction as a result of adverse reaction with the environment is called corrosion. In this study, the casing pipe for one of the wells, located in southwest of Iran, was designed in term of its strength against the imposed loads (burst, collapse, and tensile), using LandMark software package. baxsed on NACE-MR0175 standard, the reservoir fluid is in the corrosion range. In casing design, different factors such as, pore pressure, weight, and safety factor are important. The pore pressure values were validated with the values used in the casing design. Moreover, a number of important parameters in casing design such as, pore pressure changes, weight, and safety factor were analyzed. The P-110 casing pipe and the C-110 casing pipe were designed in this study. The design of the P-110 casing pipe failed due to overcoming of imposed loads on the resistance of the pipe but, the C-110 casing pipe, on the other hand, was designed successfully because of greater resistance against the imposed loads. The changes in pore pressure gradient were considered for the C-110 casing pipe. In this case, the increase of the pore pressure gradient, compared to the first condition, increased the loads; as a result, the increased loads exceeded the resistance of pipe, and consequently, the casing design failed. As well, reducing the pore pressure gradient, compared to the first condition, reduced the imposed loads; as a result, this reduction made the casing design successful. Additionally, with the use of brine pressure gradient, the casing pipe was successfully designed. The second important parameter in the designing of the C-110 casing pipe was the factor of safety. The change in safety factor will cause a change in the imposed loads; in other words, the increase of safety factors increased the imposed loads which led to the failure of the casing design. The decrease of safety factors, on the other hand, made the casing design successful. Another important parameter in casing design is weight of the casing pipe. In this analysis, the C-110 pipes, weighing 43.5, 47, and 53.5 pounds each, were analyzed. The weight of the casing pipe was in the opposite of the two previous parameters. Thus, the increase of the weight of the pipe increased the resistance of the pipe which led to the successful design of the casing pipe; and the decrease of its weight, made the casing design unsuccessful.