To gain a better understanding of cadmium (Cd) stress responses, we used proteomic approaches to investigate the proteins differentially expressed in etiolated roots of rice exposed to cadmium chloride. More than 600 protein spots from the roots were detected on the two-dimensional gel electrophoresis (2-DE) gel. Comparative analysis of three independent biological replicates revealed that the expression of 27 proteins changed by more than 1.5 fold in response to Cd. Of these proteins, sucrose synthase, putative ATP-binding cassette transporter protein, putative glyceraldehyde-3-phosphate dehydrogenase, glucanase, fructose bisphosphate aldolase and proteasome subunit alpha showed down-regulated expression patterns in response to Cd. However, S-adenosylmethionine synthetase, dimethylaniline monooxygenase, glutathione-S-transferase and dnaK-type molecular chaperone hsp70 were up-regulated upon treatment with Cd. The Cd-induced antioxidant enzyme profile alterations on the activity stained gel showed good correlation with those on the 2-DE gel.