The sponge city construction in areas with collapsible loess is faced with the risk of collapse deformation. Taking the airport industrial zone of Airport New Town in Xixian New Area as an example, the collapsibility of collapsible loess under different rainfall conditions was numerically simulated. The rainfall flood process was calculated using GPU accelerated surface water flow and transport (GAST) model, and the rainfall infiltration process was introduced to Midas GTS/NX software as the boundary condition to simulate the deformation of loess foundation. Based on the analysis of five typical loess regions with collapse deformation, it is found that the collapsibility of the five regions are all classified as grade II and above. The depth of rainwater infiltration under the most serious condition is 5.02 ~ 6.51 m, the total collapsibility and dead weight collapsibility are 468.18~1 015.56 mm and 88.99~239.03 mm respectively, which is classified as grade III collapsibility. Therefore, it is suggested that quantitative assessment and reasonable avoidance of collapsible risk should be carried out in the construction of sponge city in collapsible loess area.