Corrosion plays an important role in the integrity management of the CO2 transport pipeline, since carbon steels, the most common material utilized for pipeline construction, are susceptible to corrosion in the presence of impurities, such as water, SO2, and NO2. Autoclave tests have been used to examine the corrosion susceptibility and severity in this condition. However, studies have shown a range of corrosion rates in similar experimental conditions, and there are no standard methods for laboratory corrosion testing in dense phase CO2 with impurities. In this study, the impact of sample configuration, one of the parameters that can affect the results of the corrosion experiment, is investigated. Autoclave experiments were conducted in dense phase CO2 with O2, SO2, NO2, H2S, CH4, and H2O where the samples were placed either vertically or horizontally. Furthermore, horizontal samples were placed in different locations of the autoclave. The results showed that corrosion was observed on both sides of the vertical samples, while top side of each horizontal sample corroded more compared to the bottom side in some conditions. For horizontal samples, the corrosion rates could increase with the location from top to bottom of the autoclave depending on the combination of impurities.