The objective of this study was to explore the particle retention capability and the morphology changes of typical evergreen broad-leaved greening plants under continuous drought stress. The experiment was taken place in an open-top chamber by supplying vehicle exhaust (simulating particle pollution source) and different watering regimes on the plant, Euonymus japonicus Thunb. var. aurea-marginatus Hort, and monitoring particle accumulation and morphology changes. Two watering regimes were implemented: exhaust exposure with continuous drought (PD) and exhaust exposure with normal water supply (P). The results showed that (1) the yellowing and shedding of the old leaves of the E. japonicus var. aurea-marginatus in the group PD was 9 days earlier than that in the group P, and only the group PD presented the shedding of mature leaves and young leaves after 19 days. (2) The particle retention in each particle size fraction of group PD was 2-3 μg/cm² lower than that of group P after 35 days observation. There was no significant difference on particle retention between the two groups in the first 28 days. However, the continuous drought significantly reduced the particle retention in each particle size fraction by about 38.60%-46.54% on the 35th day. The significant change was attributed to many of the mature leaves of group PD fell off on the day of 35, which also indicated drought tolerance threshold. In conclusion, the short-term mild to moderate drought has slight effect on the particle retention ability of E. japonicus var. aurea-marginatus, while the extreme drought can accelerate the shedding of mature leaves under exhaust exposure, which may weaken its particle retention effect.