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A study was undertaken to determine the effects of different concentrations of arsenic (As) in irrigation water on Boro (dry‐season) rice (Oryza sativa) and their residual effects on the following Aman (wet‐season) rice. There were six treatments, with 0, 0.1, 0.25, 0.5, 1, and 2 mg As L⁻¹ applied as disodium hydrogen arsenate. All the growth and yield parameters of Boro rice responded positively at lower concentrations of up to 0.25 mg As L⁻¹ in irrigation water but decreased sharply at concentrations more than 0.5 mg As L⁻¹. Arsenic concentrations in grain and straw of Boro rice increased significantly with increasing concentration of As in irrigation water. The grain As concentration was in the range of 0.25 to 0.97 µg g⁻¹ and its concentration in rice straw varied from 2.4 to 9.6 µg g⁻¹ over the treatments. Residual As from previous Boro rice showed a very similar pattern in the following Aman rice, although As …