Many predictive markers for platinum-based chemotherapy have been reported, but none have been based on the results of randomized studies. We evaluated candidate predictive markers for platinum-based chemotherapy according to the mechanisms of chemoresistance to platinum drugs. Na(+), K(+)-ATPase and multidrug resistance protein 1 were reported to be related to the accumulation of platinum drugs in tumor cells. Glutathione S-transferase-pi and metallo- thionein have been related to the metabolism of platinum drugs, excision repair cross-complementing 1/2 to DNA repair systems, and p53 to apoptosis. Correlations of these markers with platinum resistance have been investigated. Considerable progress has recently been made in methods to detect these predictive markers, leading to the transition from a candidate or pathway approach to a more comprehensive "-omic approach". Comprehensively selected candidate predictive markers should be carefully evaluated to permit more efficient and more economical diagnoses. Furthermore, such markers must be validated clinically in large prospective randomized, controlled studies using standardized measurement techniques and evaluation methods in the near future.