Yellow flesh peaches (Prunus persica L.) from different Sicilian areas (Leonforte, Riesi and Maniace) were investigated for the first time for their polyphenolic composition, with consideration of both peel and flesh tissues. The qualitative and quantitative polyphenolic evaluation was determined at two different maturity stages (commercial and postharvest ripening) via chromatographic separation by using reverse‐phase HPLC‐PDA‐ESI/MS 2. This technique provides a comprehensive chromatographic evaluation of 10 compounds (hydroxycinnamates and flavonols), differently distributed in the analyzed tissues. Overall, the hydroxycinnamates were present in both pulp and peel, while flavonols resulted exclusively located in the peel. Peels were found to be richest in polyphenolics with respect to the pulps, containing up to 276 mg/kg fresh weight in Riesi commercial‐ripe peaches. Generally, the peach tissues from commercial‐ripe fruits showed higher phenolics contents than postharvest‐ripe fruits. Practical Applications It is well documented that the benefits due to the consumption of fruit can be largely attributed to the elevated content of phenolic compounds. High levels of phenolic compounds in fruits are of high importance to maintain the quality of fruits and provide consumers the health benefits of fruit consumption. Thus, the assessment of the distribution of phenolic compounds in various parts of the peach fruit and any variations due at the time of collection are considered interesting from a scientific point of view. The characterization of peach phenolics could represent a useful tool in the area of food authenticity protection since some compounds could represent specific quality markers. Moreover, a study on phenolics quantification at different ripening stages could provide useful information for assessing the fruit harvest timing in order to ensure the best fruit quality.