In this study the behavior of ascorbic, citric andmalic acids was evaluated during storage of long lifetomato (Solanum lycopersicum L.) minimally processedunder different conservation conditions. Tomatoslices were subjected to immersion in ascorbic acidof150 and 300 ppm, citric acid of 250 and 500 ppm,and water bath at 45 and 50 °C during 9 days at 4 °C.Acids were extracted with H3PO4 at 4.5 %v / vand analyzed by HPLC with mobile phase pH 2.3H2SO4 RP-C18 column, 30 cm 4.6 mm ID 5μm,flow 0.3 mL / min. Samples were evaluated at days0, 3, 6 and 9 of storage. The results indicated thatthe ascorbic acid content decreases with citric acidtreatment from 250 ppm to 50 °C. The content ofcitric and malic acids is not affected neither by heattreatment nor with ascorbic acid.