A crop rotation system combining agricultural production with phytoremediation is an economical and sustainable method of remediation of cadmium (Cd)-contaminated farmland. This study focuses on migration and transformation of Cd in rotation systems and the influencing factors. In a two-year field experiment, four rotation systems were evaluated: traditional rice and oilseed rape (TRO), low-Cd rice and oilseed rape (LRO), maize and oilseed rape (MO), and soybean and oilseed rape (SO). Oilseed rape is a remediation plant in rotation systems. Compared to 2020, the grain Cd concentrations of traditional rice, low-Cd rice, and maize in 2021 decreased by 73.8%, 65.7%, and 24.0% (below the safety limits), respectively. However, soybean increased by 71.4%. The LRO system featured the highest oil content of rapeseed (about 50%) and economic output/input ratio (1.34). Removal efficiency of total Cd in soil was 10.03% (TRO) > 8.3% (LRO) > 5.32% (SO) > 3.21% (MO). Crop uptake of Cd was influenced by bioavailability of soil Cd, and soil environmental factors regulated the bioavailable Cd. Redundancy analysis (RDA) indicated that soil nitrate‑nitrogen (NO3−-N) had a dominant impact on bioavailable Cd in soil, with variance contributions of 56.7% for paddy-upland (TRO and LRO) and 53.5% for dryland (MO and SO) rotation systems. The difference reflected that ammonium N (NH4+-N) was a secondary factor in paddy-upland rotations, while it was the available phosphorus (P) in dryland rotations, with variance contributions of 10.4% and 24.3%, respectively. The comprehensive evaluation of crop safety, production, economic benefits, and remediation efficiency revealed that the LRO system was efficient and more acceptable to local farmers, providing a new direction for the utilization and remediation of Cd-contaminated farmland. Display omitted •Rotation with oilseed rape ensures food security for succeeding rice crops.•LRO had the highest economic value, oil content, and ideal Cd removal efficiency.•Soybean and oilseed rape rotation mutually promoted Cd uptake.•Soil NO3−-N is the dominant factor influencing Cd bioavailability.•Soil Cd bioavailability is decreased by increasing available P in the dryland.