The objective of this paper was to monitor peach ripeness of 'Chimarrita' and 'Maciel' cultivars, grafted on different rootstocks, using the flesh-flesh firmness parameter, as an indicator of harvest time through equipment based on Vis/Nir spectroscopy. The orchard was installed in 2005, was "V" system trained with spacing of 5.0 x 1.5 m, and the cultivars were grafted on seven rootstocks: 'Capdeboscq', 'Flordaguard', 'Nemaguard', 'Okinawa', 'Tsukuba', 'Umezeiro' and 'Viamão'. After harvesting, the fruits were evaluated by the NIR CASE spectrophotometer, establishing categories of flesh-flesh firmness, between 40N and 60N for fruits consumed in a long term and <40N for immediate consumption. The analyzed rootstocks alter the peach ripeness of the 'Chimarrita' and 'Maciel' cultivars. The 'Umezeiro' rootstock induced early harvest for the 'Chimarrita' cultivar. The 'Nemaguard'/'Maciel' combination provides fruits with a superior harvest period than the other ones evaluated. The Vis/Nir spectroscopy is a useful tool to monitor the harvest of 'Chimarrita' and 'Maciel' cultivars.