Aims To determine the prevalence of functional alleles for drug metabolising genes in a sample of Maori and compare allele frequencies with Caucasians estimates. Procedures DNA from 60 Maori volunteers was genotyped for cytochrome P450 polymorphisms-CYP2A6, CYP2C9, CYP2C19, and CYP2D6-and allele frequencies calculated and compared with Caucasian estimates. Results Absolute allele frequency differences between Maori and Caucasian groups ranged from 1% to 16% for the polymorphisms tested. Conclusions Functional allele frequencies of drug metabolising genes differed between Maori and European groups warranting larger general population surveys. These findings may also bear thinking about when conducting pharmacogenetic studies or clinical trials in New Zealand cohorts because patients with Maori ancestry may respond differently to certain medicines based on genotype.