Prunus persica (peach tree) produces gum exudates on it trunk and fruit and its polysaccharide components (PPN and PPNF, respectively) were composed of Ara, Xyl, Man, Gal, and uronic acids in a 36:7:2:42:13 and 32:13:2:33:20 molar ratio, respectively. PPN and PPNF were homogeneous on HPSEC-MALLS and had 5,61 x 10⁶ and 6,43 x 10⁶ g.mol^-1, respectively. Methylation data on PPN showed mainly nonreducing end-units of Araf (20%) and Xylp (13%), and side chains containing 3-O- (6%) and 5-O-substituted (14%) Araf units. The galactosyl units were mainly 3,6-di-O- (19%) and 3,4,6-tri-O-substituted (14%), showing a highly branched main-chain. The ¹³C-NMR spectrum of PPN confirmed this complexity with 5 signals at d 109.5-107.5 from α-L-Araf units and a main signal at d 103.2 from the main chain of β-D-Galp units. In order to obtain a basic structure of PPN, we carried out a controlled Smith degradation followed by partial hydrolysis with 0.1 M TFA for 60 min at 100° C to yield PPNS60 (20% yield), which had Gal as its major component (85%). Methylation analysis showed much 2,3,4-Me₃-Gal derivative (45%) and its ¹³C-NMR spectrum had one C-1 main signal at d 103.8 from β-D-Galp main-chain units. The signal at d 68.4 was inverted in a ¹³C-NMR DEPT spectrum and was attributed to substituted C-6 of the β-D-Galp main-chain units. In another analysis we carried out two successive controlled Smith degradations of PPN, which produced a polysaccharide (PPNS2 / 0,45% yield) composed of Gal and Man in a 71:29 molar ratio. Methylation data showed nonreducing end-units of Gal (25%), a main chain of 3-O-linked Gal units (34%) with some of these units substituted at O-2 (21%) by side chains of 3-O-substituted Man (17%) and at O-6 (3%) by nonreducing end-units of Gal. The ¹³C-NMR spectrum of PPNF was quite similar to that PPN and had 4 signals from α-L-Araf units (d 109.5-107.5) and a prominent signal at d 103.2 from a main-chain of β-D-Galp units. Methylation data confirmed the structural similarity between these two fractions.