In climacteric fruits, the ripening process (flesh softening and epicarp coloring) appears to be due to the transition from basal ethylene production to the autocatalysis of the hormone. The stony hard (hd) peaches are unable to make this transition due to the lack of the synthesis of one of the key enzymes of the ethylene biosynthetic pathway. With the aim to explain the hd phenotype the genomic DNA of the stony hard peach Yumyeong was re-sequenced by the Illumina Genome Analyzer IIx. P. persica genotype was analysed using paired-end reads with a 30X coverage at 2x100bp to deeply investigate single nucleotide polymorphisms (SNP) and small deletion/insertion variations (DIP). All the high-throughput sequencing analysis were performed using the CLC Genomic Workbench V. 4.8 pipeline. A total of more than 52 mln of high quality reads (about 5 Gbp) were obtained; these reads were aligned against the peach reference genome (Peach V 1.0) released by IPGI (The International Peach Genome Initiative). The average coverage obtained after reads trimming was 21.8 X fold with a 93% of Peach V 1.0 coverage. In particular 16 genes (ETR2, ACS5, ACO, ETR1, ACS1, ACS, ACO1, ACO2, ACS4, ACS2, ACS, EIN2, EIN4, ACS3, ERF2, ERS1) involved in the ethylene pathway were analysed. The coding sequence and the ATG up-stream region (5000 bp) of these genes were compared with Lovell genome (a standard ripening genotype) and 11 showed differences at sequence level. This study has revealed 202 variants (SNP and DIP), 46 of them were located in the coding regions.