Late Pruning (LP) has emerged as a tool that could delay ripening and reduce the imbalance between sugars, acids and phenological compounds produced during ripening by temperature increase. The study aim was to evaluate the LP in the cv. Merlot from the Central Valley of Chile, under two temperature conditions: Ambient a High; and 3 pruning moments: Winter, budbreak; shoots 2-4 cm. During season a phenological follow-up was carried out, gas exchange and crop growth were determined. At harvest, the quality of the grapes (Brix, acidity, pH) was assessed, and the concentration of anthocyanins was determined. The increase in temperature produced an increase in the leaf temperature above 30°C, in addition to drops in AN, gs and WUEF, in addition to significantly reducing the yield per plant. The high temperature treatments presented an earlier harvest date, independent of pruning. Moreover, a lower anthocyanin concentration was determined under all high temperature treatments, which indicated that late pruning was not able to counteract the effects in Merlot. However, under current temperature conditions, pruning was able to delay the harvest by at least a week, achieving a 10% increase in anthocyanins concentration in the skin, but its effects on acidity must be evaluated.