Using HS-SPME-GC-MS, characteristics of the volatiles of 50 peaches and nectarines representing different germplasm origins were investigated. Ten of these peaches and nectarines were studied in two successive years. Eighty-four Compounds were identified. Volatile composition was relatively consistent, but the amount of total volatiles and certain individual compounds varied between years. Moreover. the composition of volatiles and their contents depended on genotypic background and germplasm origin. Total volatiles in wild peaches and a Chinese local cultivar 'Wutao' were much higher than in the other groups, All the peaches and nectarines could be classified into four groups by principal component analysis of the volatiles (excluding C-6 compounds): 'Ruipan 14' and 'Babygold 7' with high contents of lactones, Chinese wild peaches and 'Wutao' with high contents of terpenoids and esters, seven cultivars with American or European origins with high content of linalool, and others without characteristic composition of volatiles. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.