Cement kiln dust (0%-27%) was used to stabilize collapsible loess. Compaction, compressive, collapsibility, and strength tests of stabilized collapsible loess were conducted. X-ray diffraction and mercury intrusion porosimetry tests were also carried out to study the characteristics of microstructural and mineral composition for loess before and after modification. Results indicate that compression and collapsible coefficients decreased with increase in cement kiln dust (CKD) content. The unconfined compressed strength is also enhanced by CKD, showing an exponential function, and curing time has a significant impact on later strength. The mineral composition of loess is changed by adding CKD, and a better packing and more stable soil structure are formed.