In this study, three rice varieties of Shuhui498, II–32A and hybrid rice IIyou498 were chosen as the experimental materials to investigate the root growth and organic acids and amino acid secretion under two periods of cadmium stress (7 and 14 d) with three cadmium concentrations (0.5, 1.0 and 3.0 mg/L of CdCl2, 0 as control). The results showed that: In the day of 7th and 14th under cadmium stress, compared to the control, all treatments of CdCl2 decreased in the indexes of root dry weight, total root number, root surface area, root volume and root length. The difference between the cadmium streatments and the control in total root number , root length and root surface area were at significant level; when in 7 d of cadmium stresses, the contents of organic acid of three varieties were 3.44 , 3.31and 3.43 mg/g, the amino acid of three varieties were 41.07, 42.03 and 40.53 μg/g, respectively. while in 14 d of cadmium stresses, the contents of organic acid of three varieties were 3.40, 3.38, 3.33 mg/g, the amino acid of three varieties were 34.95, 35.95 and 35.28 μg/g, respectively. The difference between the CdCl2 treatments and the control reached significant level in the contents of organic acid and amino acid of three rice varieties. The content of oxalic acid was higher than malic acid in the component of organic acid secreted, The content of glycine in the secretory component was relatively high, the second were the serine and threonine. Comparison between varieties (or lines), in 7 d and 14 d of cadmium stress with 0.5 mg/L CdCl2, the contents of organic acids and amino acid were not significant difference among the three rice varieties, while IIyou498 was significantly higher than Shuhui498 and II–32A under the cadmium stress with 1.0 and 3.0 mg/L CdCl2.