In the event of Loss of Coolant Accident or Main Steam Line Break accident, a significant amount of high temperature and pressure steam will be released into the containment gas space, resulting in an increase in both temperature and pressure within the containment. To ensure safety of the reactor, HPR1000 utilizes a passive containment heat removal system (PCS) to condense steam–air mixture outside the tubes, thereby maintaining temperature and pressure stability. In order to enhance the heat transfer capability of PCS, the condensation heat transfer characteristics of steam containing non-condensing gas outside the tube bundle with different structures were investigated through CFD method. This study focused on examining the effects of tube length, diameter, arrangement, tube pitch, inclination and so on. The results indicate that the condensation heat transfer coefficient (ha) decreases as the number of tube bundle rows increases from 1 to 3 compared to vertical tube, whereas after rows exceeds 3, the ha fluctuates within a range of approximately 2%. Additionally, the heat transfer capacity of the short tube bundle is enhanced when the tube pitch reduced to 1.5 d, whereas for the long tube bundle, a larger tube pitch (3d) leads to stronger heat transfer capacity, compared with a 1 m tube bundle, the ha of 5 m tube bundle increases by 9.6%. moreover, the square arrangement outperforms the triangular arrangement at narrow tube pitch; however, the triangular arrangement is superior at wide tube pitch.