Amplified Fragment Length Polymorphism (AFLP) screening is a genome-wide genotyping strategy that has been widely used in plants and bacteria, but little has been reported concerning its use in humans. We investigated if the AFLP procedure could be coupled with high-throughput capillary electrophoresis (CE) for use in tumor diagnosis and classification. Using CE-AFLP, a series of molecular 'fingerprints' were generated for a set of gastric tumor and normal genomic DNA samples. The CE-AFLP procedure was qualitatively and quantitatively robust, and a variety of clustering tools were used to identify a specific DNA marker 'pattern' of 20 features that classified the tumor and normal samples to reasonable degrees of accuracy (Sensitivity 95%, Specificity 80%). The CE-AFLP-based approach also correctly classified 16 tumor samples, which in a previous study had exhibited no detectable genomic aberrations by comparative genome hybridization (CGH). This is the first reported application of CE-AFLP screening in tumor diagnosis. As the procedure is relatively inexpensive and requires minimal prior sequence knowledge and biological material, we suggest that CE-AFLP-based protocols may represent a promising new approach for DNA-based cancer screening and diagnosis.