Human cytochrome P450(CYP 450) enzymes mediate over 60% of the phase I-dependent metabolism of clinical drugs. They are also known for the polymorphism functions that have significant impacts on the enzyme activities. In this study, a web-server called SCYPPred was developed for predicting human cytochrome P450 SNPs (Single Nucleotide Polymorphisms) based on the SVM flanking sequence method; SCYPPred can rapidly yield the desired results by using the amino acid sequences information alone. The web-server is accessible to the public at http://snppred.sjtu.edu.cn. Hopefully SCYPPred could be a useful bioinformatics tool for elucidating the mutation probability of a specific CYP450 enzyme.