The composition and content of main volatile flavor components in fresh peach, freeze-dried peach and lyophilizer cold trap water were compared and analyzed by SPME-GC/MS. The results showed that there were 26, 18 and 11 volatile flavor components in fresh peach, freeze-dried peach and cold trap water, respectively. They mainly included aldehydes, alcohols, esters, hydrocarbons, heterocyclics and ethers. Volatile flavor components in fresh peaches changed and migrated during freeze-drying. The retained volatile flavor components in the freeze-dried peach mainly included hexanal, (E)-2-heptenal, (E)-2-octenal, benzaldehyde, pentanol, hexanol, (E)-2-hexen-1-ol, hexyl acetate, hexyl acetate, and γ-caprolactone. Furfural and diethylene glycol ether completely migrated into the cold trap water; the contents of the freeze-dried peach slices were (E)-2-hexenal, linalool, (E)-acetic acid-2.-hexen-1-ol ester. The content of (E)-2-hexenal, linalool, (E)-acetic acid-2-hexen-1-ol in freeze-dried peach were increased. The newly generated volatile flavor components after freeze-drying were isooctyl acetate, 2,7-dimethylnaphthalene, 1,6-dimethylnaphthalene, and 2,3-dimethylnaphthalene.