In order to examine the impact of atmospheric deposition on the flux and speciation of cadmium (Cd) input into paddy soils, atmospheric deposition flux monitoring and reciprocal translocation experiments of paddy soils were conducted at three distances from a large-scale smelter: 36 km, a background site; 6 km, a medium deposition; and 1 km, a high deposition site. Heavy metal continuous extraction methodology was used to investigate the atmospheric deposition of Cd form and its transformation in paddy soil profiles with varying degrees of contamination. The findings indicated that the annual atmospheric deposition fluxes of Cd in the high, medium and background sites were 12.20, 2.90 and 0.84 mg/m², respectively, and the proportions of exchangeable and reducible Cd were significantly higher than those in the paddy soils, and a significant negative correlation was identified between the deposition flux and the distance from the smelting plant. When the soils in the background site were exposed to the medium and high deposition sites, their top soil (0-2 cm) Cd concentrations increased significantly by 12% and 28%, whereas the soils in the medium and high deposition sites had a 20% decrease in the 0-2 cm soil Cd concentration after being transferred to the background site. Atmospheric deposition of Cd significantly increased the concentrations and proportions of Cd in both the exchangeable and reducible fractions within the soil profile (0-2 cm), and its contribution to the exchangeable fractions of Cd in the top soils (0-2 cm) of both the high and medium deposition sites significantly increased by 17%-45%, but it did not have a significant effect on the total amount and speciation of Cd in the soil layers >4 cm in depth. In conclusion, the findings of this experiment indicate that highly reactive atmospheric deposition of Cd can significantly increase the bioavailability of soil Cd, thereby elevating the potential for its accumulation in crops.